CVE-2026-113659
ApostropheCMS: Client-side Prototype Pollution in apos.http.parseQuery leading to DOM-based XSS against authenticated users
MEDIUM 6.1EPSS 0.3%
ApostropheCMS is an open-source Node.js content management system. Prior to 4.33.0, an unauthenticated attacker can send a crafted link whose query string is automatically parsed by apos.http.parseQuery when an authenticated victim loads a page with the admin bundle. The parser accepts the special __proto__, constructor, and prototype path keys, allowing browser prototype mutation that can reach an unsafe DOM sink and execute script in the victim's session; anonymous visitors do not load the affected admin context. This issue is fixed in version 4.33.0.
- Affected
- apostrophecms · apostrophe
- CVSS v3.1 GITHUB
- 6.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS
- 0.34% chance of exploitation in the next 30 days, 28th percentile
- Published
- 2026-10-20
- Updated
- 2026-10-28
Proof-of-concept exploits (1)
CVE references
- apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ceREFERENCE
- apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350REFERENCE
- apostrophecms/apostrophe/releases/tag/apostrophe@4.33.0REFERENCE
- apostrophecms/apostrophe/security/advisories/GHSA-m2m5-rw3w-cwmjREFERENCE