{"id":"CVE-2026-55661","aliases":["EUVD-2026-41141","GHSA-2vcc-5v34-9jc8"],"status":"published","title":"TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes","description":"Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and  tinacms 3.9.3,  rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:text/html URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into href/src and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers. This issue is fixed in versions @tinacms/mdx 2.1.7 and  tinacms 3.9.3.","severity":{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00405,"percentile":0.35202,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-79","CWE-87"],"published":"2026-06-18T13:07:05Z","modified":"2026-10-28T02:30:41Z","fixes":[{"ecosystem":"npm","package":"tinacms","fixed_in":["3.9.3"],"sources":["ghsa","osv"]},{"ecosystem":"npm","package":"@tinacms/mdx","fixed_in":["2.1.7"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"npm","package":"tinacms","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.9.3"}]}]},{"source":"ghsa","ecosystem":"npm","package":"@tinacms/mdx","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.7"}]}]},{"source":"osv","ecosystem":"npm","package":"tinacms","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"3.9.3"}]}]},{"source":"osv","ecosystem":"npm","package":"@tinacms/mdx","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.1.7"}]}]}],"products":[{"vendor":"tinacms","product":"@tinacms/mdx"},{"vendor":"tinacms","product":"tinacms"}],"references":[{"url":"https://github.com/tinacms/tinacms/security/advisories/GHSA-2vcc-5v34-9jc8","tags":["x_refsource_CONFIRM","advisory","web"]},{"url":"https://github.com/tinacms/tinacms/pull/7056","tags":["x_refsource_MISC","fix","web"]},{"url":"https://github.com/advisories/GHSA-2vcc-5v34-9jc8"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55661.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55661","tags":["advisory"]},{"url":"https://github.com/tinacms/tinacms","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-55661","title":"TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes","description":"Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and  tinacms 3.9.3,  rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:text/html URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into href/src and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers. This issue is fixed in versions @tinacms/mdx 2.1.7 and  tinacms 3.9.3.","status":"published","published":"2026-07-01T20:44:50.116Z","modified":"2026-07-06T14:39:33.214Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-79","CWE-87"],"updated_at":"2026-11-02T14:20:11.925815Z"}],"euvd":[{"id":"EUVD-2026-41141","description":"Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and  tinacms 3.9.3,  rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:text/html URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into href/src and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers. This issue is fixed in versions @tinacms/mdx 2.1.7 and  tinacms 3.9.3.","status":"published","published":"2026-07-01T20:44:50Z","modified":"2026-07-06T14:39:33Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"updated_at":"2026-11-02T18:20:13.172179Z"}],"ghsa":[{"id":"GHSA-2vcc-5v34-9jc8","title":"TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes","description":"TinaCMS rich-text parsing and the default link/image renderers did not sanitize the `url` field on Slate link/image nodes. Content containing `javascript:` or `data:text/html` URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into `href`/`src` and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers.\n\nFixed in https://github.com/tinacms/tinacms/pull/7056 via a `sanitizeUrl()` helper (case-insensitive, whitespace/control-character-normalized scheme allow-list) applied recursively to Slate trees at parse time and in the default rich-text rendering.","status":"published","published":"2026-06-18T13:07:05Z","modified":"2026-06-18T13:07:05Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79","CWE-87"],"updated_at":"2026-11-02T14:40:29.43528Z"}],"nvd":[{"id":"CVE-2026-55661","description":"Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and  tinacms 3.9.3,  rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:text/html URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into href/src and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers. This issue is fixed in versions @tinacms/mdx 2.1.7 and  tinacms 3.9.3.","status":"published","published":"2026-07-01T21:17:04.09Z","modified":"2026-07-06T16:16:34.977Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/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":"medium","assessor":"secondary"}],"cwes":["CWE-79","CWE-87"],"updated_at":"2026-11-02T14:12:27.199837Z"}],"osv":[{"id":"CVE-2026-55661","title":"TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes","description":"Tina is a headless content management system. In versions prior to @tinacms/mdx 2.1.7 and  tinacms 3.9.3,  rich-text parsing and the default link/image renderers did not sanitize the url field on Slate link/image nodes. Content containing javascript: or data:text/html URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into href/src and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers. This issue is fixed in versions @tinacms/mdx 2.1.7 and  tinacms 3.9.3.","status":"published","published":"2026-07-01T20:44:50.116Z","modified":"2026-10-28T02:30:41.223515873Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79","CWE-87"],"updated_at":"2026-11-02T15:45:11.22012Z"},{"id":"GHSA-2vcc-5v34-9jc8","title":"TinaCMS rich-text (slatejson) rendering does not sanitize link/image URLs, allowing stored XSS via dangerous URL schemes","description":"TinaCMS rich-text parsing and the default link/image renderers did not sanitize the `url` field on Slate link/image nodes. Content containing `javascript:` or `data:text/html` URLs — including case-variant, whitespace-padded, and control-character-obfuscated forms — is rendered into `href`/`src` and executes when the content is viewed. Any actor able to author rich-text content (for example a lower-privileged editor, or imported/external content) can achieve stored XSS against editors and site viewers.\n\nFixed in https://github.com/tinacms/tinacms/pull/7056 via a `sanitizeUrl()` helper (case-insensitive, whitespace/control-character-normalized scheme allow-list) applied recursively to Slate trees at parse time and in the default rich-text rendering.","status":"published","published":"2026-06-18T13:07:05Z","modified":"2026-09-10T03:50:55.365499184Z","cvss":[{"version":"4.0","score":4.8,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N","level":"medium"}],"cwes":["CWE-79","CWE-87"],"updated_at":"2026-11-02T15:46:34.700741Z"}]}}