CVE-2026-67351

Serendipity before 2.6.1 contains an authentication context confusion vulnerability where password validation and session loading operate independently without ensuring both use the same user record. An authenticated Editor can create a username collision with an Administrator account and obtain administrative privileges by logging in with their own password while the session loads the Administrator's account data.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/s9y/Serendipity/security/advisories/GHSA-v645-243f-jwgh
https://www.vulncheck.com/advisories/serendipity-authentication-bypass-via-username-collision
https://github.com/s9y/Serendipity/security/advisories/GHSA-v645-243f-jwgh

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-30 14:17

Updated : 2026-07-31 23:17

NVD link : CVE-2026-67351

Mitre link : CVE-2026-67351

CVE.ORG link : CVE-2026-67351

JSON object : View

Products Affected

No product.

CWE

CWE-304

Missing Critical Step in Authentication

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