XSS in Apostrophecms Apostrophe
CVE-2026-113659
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Apostrophecms Apostrophe — versions < 4.33.0
Weakness classification (CWE)
References
- github.com/apostrophecms/apostrophe/security/advisories/GHSA-m2m5-rw3w-cwmj
- github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed09438…
- github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130…
- github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.33.0
Frequently asked questions
- What is CVE-2026-113659?
- CVE-2026-113659 is a medium-severity vulnerability in Apostrophecms Apostrophe, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-10-20.
- How severe is CVE-2026-113659?
- Medium severity. CVSS v3 base score is 6.1 out of 10.