CVE-2026-84371
ApostropheCMS: Stored XSS via SVG SMIL URI-list scheme-policy bypass
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
ApostropheCMS is an open-source Node.js content management system, and sanitize-html provides a simple HTML sanitizer with a clear API. From version 1.9.0 until version 2.17.7, packages/sanitize-html/index.js validates an animation value attribute as one flat URL and does not recognize that attributeName selecting href or xlink:href gives the sibling values, from, to, or by attribute SVG SMIL URL semantics. In configurations that allow the animate, animateColor, animateMotion, animateTransform, or set elements, a values list can begin with a safe fragment and contain a later executable destination that survives allowedSchemesAppliedToAttributes checking. When the sanitized SVG is rendered, the browser can copy that later destination into the live link, and a victim who activates the link can execute script in the application's origin. This issue is fixed in version 2.17.7.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVDNVD · Deferred | 3.1 | Medium5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.30% · top 77% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.4.
Weakness
Affected products
- affected >= 1.9.0, < 2.17.7
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npmsanitize-htmlGHSA-g8qq-57p8-ggw5 (opens in a new tab)
References (5)
- https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-g8qq-57p8-ggw5 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/apostrophecms/apostrophe/pull/5552 (opens in a new tab)x_refsource_MISC
- https://github.com/apostrophecms/apostrophe/commit/1135516a1a4a8f9638641c460488a43d8af20081 (opens in a new tab)x_refsource_MISC
- https://github.com/apostrophecms/apostrophe/commit/38ff1106c8176b16c2da9872acd9b449adcbb949 (opens in a new tab)x_refsource_MISC
- https://github.com/apostrophecms/apostrophe/blob/main/packages/sanitize-html/CHANGELOG.md (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-g8qq-57p8-ggw5 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-84371)Record last updated .