CVE-2026-35569

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.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.3 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/Chittu13/cve-research/tree/main/CVE-2026-35569
https://github.com/apostrophecms/apostrophe/commit/0e57dd07a56ae1ba1e3af646ba026db4d0ab5bb3	Patch
https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-855c-r2vq-c292	Exploit Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:apostrophecms:apostrophecms:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-15 20:16

Updated : 2026-06-17 10:40

NVD link : CVE-2026-35569

Mitre link : CVE-2026-35569

CVE.ORG link : CVE-2026-35569

JSON object : View

Products Affected

apostrophecms

apostrophecms

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-116

Improper Encoding or Escaping of Output

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