ApostropheCMS: Stored XSS in SEO Fields Leads to Authenticated API Data Exposure in ApostropheCMS (apostrophecms apostrophe)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.30 % · percentile 22 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Modified
Description
ApostropheCMS is an open-source Node.js content management system. Versions 4.28.0 and prior contain a stored cross-site scripting vulnerability in SEO-related fields (SEO Title and Meta Description), where user-controlled input is rendered without proper output encoding into HTML contexts including <title> tags, <meta> attributes, and JSON-LD structured data. An attacker can inject a payload such as "></title><script>alert(1)</script> to break out of the intended HTML context and execute arbitrary JavaScript in the browser of any authenticated user who views the affected page. This can be leveraged to perform authenticated API requests, access sensitive data such as usernames, email addresses, and roles via internal APIs, and exfiltrate it to an attacker-controlled server. This issue has been fixed in version 4.29.0.
Weaknesses (CWE)
- CWE-79 — Improper Neutralization of Input During Web Page Generation
- CWE-116 — Improper Encoding or Escaping of Output
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N | GitHub_M |
| CVSS 3.1 | HIGH 8.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-855c-r2vq-c292 — Stored XSS in SEO Fields Leads to Authenticated API Data Exposure in ApostropheCMS
European references
- ENISA EUVD · EUVD-2026-23106
- GCVE · GCVE-0-2026-35569
Affected configurations (NVD CPE)
cpe:2.3:a:apostrophecms:apostrophecms:*:*:*:*:*:*:*:*< 4.29.0
Affected products
| Product | Versions |
|---|---|
| apostrophecms · apostrophe | affected < 4.29.0 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |