CVE-2026-67351

HIGH CVSS 4.0: 8.7 EPSS 0.37%
Updated Aug 01, 2026
S9Y
Parameter Value
CVSS 8.7 (HIGH)
Affected Versions before 2.6.1
Fixed In 2.6.1
Type CWE-304
Vendor S9Y
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v4.0

Weakness Type (CWE)

Vulnerable Products 1

Configuration From (including) Up to (excluding)
S9y Serendipity
cpe:2.3:a:s9y:serendipity:*:*:*:*:*:*:*:*
2.6.1