CVE-2026-89022
Published:September 15, 2026
Updated:October 13, 2026
BookStack before 26.05.5 contains an authentication bypass vulnerability in its social login implementation that allows unauthenticated attackers to sign in as arbitrary users by authenticating through a different social provider sharing the same driver_id namespace. Attackers can authenticate at one enabled social provider using a user ID that matches an account linked to a different social provider, bypassing credential verification entirely because the SocialAuthService::handleLoginCallback query ignores the driver column when retrieving linked account records.
Affected Packages
https://github.com/BookStackApp/BookStack.git (GITHUB):
Affected version(s) >=v0.5.0 <v26.05.5Fix Suggestion:
Update to version v26.05.5ssddanbrown/bookstack (PHP):
Affected version(s) >=v0.5.0 <v26.05.5Fix Suggestion:
Update to version v26.05.5Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
9.1
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.4
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Authentication Bypass by Spoofing
EPSS
Base Score:
0.46