CVE-2026-112958 · GHSA-7jg5-frgc-c67w
ApostropheCMS: Stored XSS via Unescaped Widget Style Attribute Serialization
- Risk score
- 47/100
- CVSS
- 5.4 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 20 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- ApostropheCMS is an open-source Node.js content management system. Prior to 4.34.0, a project-defined free-form widget style field can carry an editor-controlled quote into an inline style attribute because the wrapper serializer does not apply HTML-attribute encoding. The quote can terminate the style attribute and i…
- Affected
- apostrophe (npm) < 4.34.0
- Fix
- Upgrade apostrophe to 4.34.0 or later.
- Exploitation
- Public proof of concept
Why it is Yellow
- CVSS 5.4 medium
- Public exploit or proof of concept referenced
- On your watchlist: npm
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| apostrophe | npm | < 4.34.0 | 4.34.0 |
References
- https://github.com/advisories/GHSA-7jg5-frgc-c67w
- https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-7jg5-frgc-c67w
- https://nvd.nist.gov/vuln/detail/CVE-2026-112958
- https://github.com/apostrophecms/apostrophe/commit/06e4b377f3c360f9e89c32dccd7e505ad5ddf498
- https://github.com/apostrophecms/apostrophe/commit/40b989b1a9dd23d30029b8ce7668634265cfe5ea
- https://github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.34.0
- https://github.com/advisories/GHSA-7jg5-frgc-c67w
Original description
ApostropheCMS is an open-source Node.js content management system. Prior to 4.34.0, a project-defined free-form widget style field can carry an editor-controlled quote into an inline style attribute because the wrapper serializer does not apply HTML-attribute encoding. The quote can terminate the style attribute and inject executable attributes when published content, or an affected draft viewed by a higher-privileged user, is rendered. This issue is fixed in version 4.34.0.
Last activity 20 Oct 2026. Patch Forecast updates every hour.