{"id":"CVE-2026-45753","aliases":["DEBIAN-CVE-2026-45753","EUVD-2026-44344","GHSA-hhg7-c65m-h7ff","UBUNTU-CVE-2026-45753"],"status":"published","title":"Symfony: HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — javascript: URI Survives Sanitization (XSS)","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","severity":{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00253,"percentile":0.16917,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-184","CWE-79"],"published":"2026-05-28T16:43:27Z","modified":"2026-10-28T02:30:55Z","fixes":[{"ecosystem":"Packagist","package":"symfony/html-sanitizer","fixed_in":["6.4.40","7.4.12","8.0.12"],"sources":["ghsa","osv"]},{"ecosystem":"Packagist","package":"symfony/symfony","fixed_in":["6.4.40","7.4.12","8.0.12"],"sources":["ghsa","osv"]},{"ecosystem":"Debian:13","package":"symfony","fixed_in":["6.4.41+dfsg-0+deb13u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"symfony","fixed_in":["7.4.12+dfsg-1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"Packagist","package":"symfony/html-sanitizer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.4.40"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/html-sanitizer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.0.0"},{"fixed":"7.4.12"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/html-sanitizer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.4.40"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.0.0"},{"fixed":"7.4.12"}]}]},{"source":"ghsa","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.4.41+dfsg-0+deb13u1"}]}],"versions":["6.4.21+dfsg-2","6.4.21+dfsg-2+deb13u1","6.4.24+dfsg-1","6.4.25+dfsg-1","6.4.40+dfsg-0+deb13u1"]},{"source":"osv","ecosystem":"Debian:14","package":"symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.4.12+dfsg-1"}]}],"versions":["6.4.21+dfsg-2","6.4.24+dfsg-1","6.4.25+dfsg-1","7.0.4+dfsg-1","7.0.5+dfsg-1","7.0.6+dfsg-1","7.0.7+dfsg-1","7.1.0~beta1+dfsg-1","7.1.0~rc1+dfsg-1","7.1.2+dfsg-1","7.1.3+dfsg-1","7.1.4+dfsg-1","7.1.5+dfsg-1","7.2.0~beta1+dfsg-1","7.2.0~beta2+dfsg-1","7.2.0~rc1+dfsg-1","7.2.1+dfsg-1","7.2.2+dfsg-1","7.2.3+dfsg-1","7.2.4+dfsg-1","7.2.5+dfsg-1","7.2.6-1","7.3.0+dfsg-1","7.3.0~beta1+dfsg-1","7.3.0~beta2+dfsg-1","7.3.0~rc1+dfsg-1","7.3.1+dfsg-1","7.3.2+dfsg-1","7.3.3+dfsg-1","7.3.4+dfsg-1","7.3.5-1","7.4.0+dfsg-1","7.4.0+dfsg-2","7.4.0~beta1-1","7.4.0~beta1-2","7.4.0~beta2+dfsg-1","7.4.0~beta2+dfsg-2","7.4.0~beta2+dfsg-3","7.4.0~rc1+dfsg-1","7.4.0~rc2+dfsg-1","7.4.0~rc3+dfsg-1","7.4.10+dfsg-1","7.4.2+dfsg-1","7.4.2+dfsg-2","7.4.3+dfsg-1","7.4.4+dfsg-1","7.4.5+dfsg-1","7.4.6+dfsg-1","7.4.6+dfsg-2","7.4.7+dfsg-1","7.4.8+dfsg-1","7.4.9+dfsg-1"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/html-sanitizer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.4.40"}]}],"versions":["v6.1.0","v6.1.11","v6.1.9","v6.2.0","v6.2.0-BETA1","v6.2.0-RC1","v6.2.2","v6.2.5","v6.2.7","v6.3.0","v6.3.0-BETA1","v6.3.0-RC1","v6.3.12","v6.3.4","v6.3.7","v6.4.0","v6.4.0-BETA1","v6.4.0-BETA2","v6.4.0-RC1","v6.4.12","v6.4.13","v6.4.17","v6.4.18","v6.4.21","v6.4.24","v6.4.25","v6.4.28","v6.4.3","v6.4.35","v6.4.4","v6.4.7","v6.4.8"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/html-sanitizer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"7.0.0"},{"fixed":"7.4.12"}]}],"versions":["v7.0.0","v7.0.3","v7.0.4","v7.0.7","v7.0.8","v7.1.0","v7.1.0-BETA1","v7.1.0-RC1","v7.1.1","v7.1.10","v7.1.11","v7.1.5","v7.1.6","v7.2.0","v7.2.0-BETA1","v7.2.0-RC1","v7.2.2","v7.2.3","v7.2.6","v7.2.9","v7.3.0","v7.3.0-BETA1","v7.3.0-RC1","v7.3.2","v7.3.3","v7.3.6","v7.4.0","v7.4.0-BETA1","v7.4.0-BETA2","v7.4.0-RC1","v7.4.7","v7.4.8"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/html-sanitizer","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"8.0.0"},{"fixed":"8.0.12"}]}],"versions":["v8.0.0","v8.0.7","v8.0.8"]},{"source":"osv","ecosystem":"Packagist","package":"symfony/symfony","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.1.0"},{"fixed":"6.4.40"}]}],"versions":["v6.1.0","v6.1.1","v6.1.10","v6.1.11","v6.1.12","v6.1.2","v6.1.3","v6.1.4","v6.1.5","v6.1.6","v6.1.7","v6.1.8","v6.1.9","v6.2.0","v6.2.0-BETA1","v6.2.0-BETA2","v6.2.0-BETA3","v6.2.0-RC1","v6.2.0-RC2","v6.2.1","v6.2.10","v6.2.11","v6.2.12","v6.2.13","v6.2.14","v6.2.2","v6.2.3","v6.2.4","v6.2.5","v6.2.6","v6.2.7","v6.2.8","v6.2.9","v6.3.0","v6.3.0-BETA1","v6.3.0-BETA2","v6.3.0-BETA3","v6.3.0-RC1","v6.3.0-RC2","v6.3.1","v6.3.10","v6.3.11","v6.3.12","v6.3.2","v6.3.3","v6.3.4","v6.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Advisory","advisory","web"]},{"url":"https://github.com/symfony/symfony/commit/487728e7e180a674a6d4c01bd0cb56161cc441b7","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/symfony/symfony/releases/tag/v6.4.40","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://github.com/symfony/symfony/releases/tag/v7.4.12","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://github.com/symfony/symfony/releases/tag/v8.0.12","tags":["x_refsource_MISC","Product","Release Notes","web"]},{"url":"https://github.com/symfony/symfony/commit/26a598fcfc4f903cc55ff202f642ee621839825e","tags":["web"]},{"url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/html-sanitizer/CVE-2026-45753.yaml","tags":["web"]},{"url":"https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-45753.yaml","tags":["web"]},{"url":"https://symfony.com/cve-2026-45753","tags":["web"]},{"url":"https://github.com/advisories/GHSA-hhg7-c65m-h7ff"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45753.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45753","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-45753","tags":["advisory"]},{"url":"https://github.com/symfony/symfony","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2026-45753","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-45753","tags":["report"]},{"url":"https://symfony.com/blog/cve-2026-45753-htmlsanitizer-urlattributesanitizer-omits-action-formaction-poster-cite-javascript-uri-survives-sanitization-xss","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-45753","title":"Symfony: HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — javascript: URI Survives Sanitization (XSS)","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","status":"published","published":"2026-07-14T18:21:13.644Z","modified":"2026-07-14T18:39:28.564Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"low","assessor":"cna"}],"cwes":["CWE-79","CWE-184"],"updated_at":"2026-11-02T13:46:43.922571Z"}],"euvd":[{"id":"EUVD-2026-44344","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","status":"published","published":"2026-07-14T18:21:13Z","modified":"2026-07-14T18:39:28Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"low"}],"updated_at":"2026-11-02T18:19:59.200665Z"}],"ghsa":[{"id":"GHSA-hhg7-c65m-h7ff","title":"Symfony's HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — `javascript`: URI Survives Sanitization (XSS)","description":"### Description\n\n`symfony/html-sanitizer` lets applications sanitise untrusted HTML. `UrlAttributeSanitizer` is the visitor responsible for validating URL-valued attributes and stripping dangerous schemes from them; it runs on every element regardless of configuration. Whether an attribute is *kept* is decided by the element/attribute allow-list; validating the *scheme* of a URL attribute is solely `UrlAttributeSanitizer`'s responsibility.\n\n`UrlAttributeSanitizer::getSupportedAttributes()` returned only `['src', 'href', 'lowsrc', 'background', 'ping']`. The HTML URL-valued attributes `action` (`\u003cform\u003e`), `formaction` (`\u003cbutton\u003e`, `\u003cinput type=image\u003e`), `poster` (`\u003cvideo\u003e`) and `cite` (`\u003cblockquote\u003e`, `\u003cq\u003e`, `\u003cdel\u003e`, `\u003cins\u003e`) were missing from that list, so `DomVisitor` never invoked scheme validation for them. As a result, when a configuration admits one of those attributes, a `javascript:` URI in it survived sanitisation.\n\n### Conditions for exploitation\n\n`allowSafeElements()` is **not** affected: `\u003cform\u003e` and the `formaction` attribute are both flagged unsafe in `W3CReference`, and `allowElement('form')` resets the element's attribute list. Reaching the vulnerable attributes requires a deliberately permissive configuration, for example:\n\n* `\u003cform\u003e` + `action`: `allowElement('form', '*')`, `allowElement('form', ['action', …])`, `allowElement('form')-\u003eallowAttribute('action', 'form')`, or the `allowStaticElements()` preset (whose docblock already warns the output \"may still contain other dangerous behaviors\");\n* `\u003cbutton\u003e` / `\u003cinput type=image\u003e` + `formaction`: `allowElement(…, '*')`, `allowAttribute('formaction', …)`, or `allowStaticElements()`;\n* `\u003cblockquote\u003e` / `\u003cq\u003e` / `\u003cdel\u003e` / `\u003cins\u003e` + `cite`, or `\u003cvideo\u003e` + `poster`: similarly via `'*'`, `allowAttribute()`, or `allowStaticElements()`.\n\nFor the `action` / `formaction` cases the victim must additionally submit the form or click the button.\n\n### Resolution\n\n`UrlAttributeSanitizer` now also handles `action`, `formaction`, `cite` and `poster`. `action` / `formaction` / `cite` are validated against the link schemes (like `\u003ca href\u003e`, so `javascript:` is rejected and `data:` is dropped too); `poster` is validated against the media schemes (so `data:` images keep working). The behaviour of `\u003ca href\u003e` and `\u003cimg src\u003e` is unchanged.\n\nOne behaviour change to be aware of: a relative `action=\"/submit\"` on an allowed `\u003cform\u003e` is now dropped by default (the same as `\u003ca href\u003e` / `\u003cimg src\u003e` today); `-\u003eallowRelativeLinks()` re-enables it.\n\nThe patch for this issue is available [here](https://github.com/symfony/symfony/commit/26a598fcfc4f903cc55ff202f642ee621839825e) for branch 6.4.\n\n### Credits\n\nSymfony would like to thank Himanshu Anand and Rémi Pelloux for reporting the issue and Nicolas Grekas for providing the fix.","status":"published","published":"2026-05-28T16:43:27Z","modified":"2026-05-28T16:43:28Z","cvss":[{"version":"4.0","score":1.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U","level":"low"}],"cwes":["CWE-79","CWE-184"],"updated_at":"2026-11-02T14:40:14.666177Z"}],"nvd":[{"id":"CVE-2026-45753","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","status":"published","published":"2026-07-14T19:17:07.633Z","modified":"2026-07-15T13:44:21.307Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"low","assessor":"secondary"},{"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":"primary"}],"cwes":["CWE-79","CWE-184"],"updated_at":"2026-11-02T14:12:29.879716Z"}],"osv":[{"id":"CVE-2026-45753","title":"Symfony: HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — javascript: URI Survives Sanitization (XSS)","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","status":"published","published":"2026-07-14T18:21:13.644Z","modified":"2026-10-28T02:30:55.56062898Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"low"}],"cwes":["CWE-184","CWE-79"],"updated_at":"2026-11-02T15:45:05.525666Z"},{"id":"DEBIAN-CVE-2026-45753","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","status":"published","published":"2026-07-14T19:17:07.633Z","modified":"2026-10-01T03:03:14.716653544Z","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":"2026-11-02T15:45:55.669088Z"},{"id":"GHSA-hhg7-c65m-h7ff","title":"Symfony's HtmlSanitizer UrlAttributeSanitizer Omits action/formaction/poster/cite — `javascript`: URI Survives Sanitization (XSS)","description":"### Description\n\n`symfony/html-sanitizer` lets applications sanitise untrusted HTML. `UrlAttributeSanitizer` is the visitor responsible for validating URL-valued attributes and stripping dangerous schemes from them; it runs on every element regardless of configuration. Whether an attribute is *kept* is decided by the element/attribute allow-list; validating the *scheme* of a URL attribute is solely `UrlAttributeSanitizer`'s responsibility.\n\n`UrlAttributeSanitizer::getSupportedAttributes()` returned only `['src', 'href', 'lowsrc', 'background', 'ping']`. The HTML URL-valued attributes `action` (`\u003cform\u003e`), `formaction` (`\u003cbutton\u003e`, `\u003cinput type=image\u003e`), `poster` (`\u003cvideo\u003e`) and `cite` (`\u003cblockquote\u003e`, `\u003cq\u003e`, `\u003cdel\u003e`, `\u003cins\u003e`) were missing from that list, so `DomVisitor` never invoked scheme validation for them. As a result, when a configuration admits one of those attributes, a `javascript:` URI in it survived sanitisation.\n\n### Conditions for exploitation\n\n`allowSafeElements()` is **not** affected: `\u003cform\u003e` and the `formaction` attribute are both flagged unsafe in `W3CReference`, and `allowElement('form')` resets the element's attribute list. Reaching the vulnerable attributes requires a deliberately permissive configuration, for example:\n\n* `\u003cform\u003e` + `action`: `allowElement('form', '*')`, `allowElement('form', ['action', …])`, `allowElement('form')-\u003eallowAttribute('action', 'form')`, or the `allowStaticElements()` preset (whose docblock already warns the output \"may still contain other dangerous behaviors\");\n* `\u003cbutton\u003e` / `\u003cinput type=image\u003e` + `formaction`: `allowElement(…, '*')`, `allowAttribute('formaction', …)`, or `allowStaticElements()`;\n* `\u003cblockquote\u003e` / `\u003cq\u003e` / `\u003cdel\u003e` / `\u003cins\u003e` + `cite`, or `\u003cvideo\u003e` + `poster`: similarly via `'*'`, `allowAttribute()`, or `allowStaticElements()`.\n\nFor the `action` / `formaction` cases the victim must additionally submit the form or click the button.\n\n### Resolution\n\n`UrlAttributeSanitizer` now also handles `action`, `formaction`, `cite` and `poster`. `action` / `formaction` / `cite` are validated against the link schemes (like `\u003ca href\u003e`, so `javascript:` is rejected and `data:` is dropped too); `poster` is validated against the media schemes (so `data:` images keep working). The behaviour of `\u003ca href\u003e` and `\u003cimg src\u003e` is unchanged.\n\nOne behaviour change to be aware of: a relative `action=\"/submit\"` on an allowed `\u003cform\u003e` is now dropped by default (the same as `\u003ca href\u003e` / `\u003cimg src\u003e` today); `-\u003eallowRelativeLinks()` re-enables it.\n\nThe patch for this issue is available [here](https://github.com/symfony/symfony/commit/26a598fcfc4f903cc55ff202f642ee621839825e) for branch 6.4.\n\n### Credits\n\nSymfony would like to thank Himanshu Anand and Rémi Pelloux for reporting the issue and Nicolas Grekas for providing the fix.","status":"published","published":"2026-05-28T16:43:27Z","modified":"2026-09-10T03:51:06.023129963Z","cvss":[{"version":"4.0","score":1.2,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U","level":"low"}],"cwes":["CWE-184","CWE-79"],"updated_at":"2026-11-02T15:46:49.28217Z"},{"id":"UBUNTU-CVE-2026-45753","description":"Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0-BETA1 until 6.4.40, 7.4.12, and 8.0.12, UrlAttributeSanitizer::getSupportedAttributes() omits URL-valued attributes including action, formaction, poster, and cite, so configurations that admit those attributes can leave javascript: URIs unsanitized and enable XSS when the resulting HTML is rendered or a victim submits a form or clicks a button. This issue is fixed in versions 6.4.40, 7.4.12, and 8.0.12.","status":"published","published":"2026-07-14T19:17:00Z","modified":"2026-10-17T13:00:12.812782321Z","cvss":[{"version":"4.0","score":2.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"low"},{"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":"2026-11-02T16:56:26.396868Z"}]}}