CVE-2026-89022
BookStack < 26.05.5 Authentication Bypass via Social Login Provider Confusion
CVSS Score
7.4
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-290 |
| Vendor | bookstackapp |
| Product | bookstack |
| Published | Sep 15, 2026 |
| Last Updated | Sep 15, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
bookstackapp / bookstack
0 < 26.05.5
References
Credits
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