Description
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.
Published: 2026-09-15
Score: 9.1 Critical
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

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Advisories

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History

Tue, 15 Sep 2026 19:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Tue, 15 Sep 2026 18:45:00 +0000

Type Values Removed Values Added
First Time appeared Bookstackapp
Bookstackapp bookstack
Vendors & Products Bookstackapp
Bookstackapp bookstack

Tue, 15 Sep 2026 16:30:00 +0000

Type Values Removed Values Added
Description 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.
Title BookStack < 26.05.5 Authentication Bypass via Social Login Provider Confusion
Weaknesses CWE-290
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

cvssV4_0

{'score': 9.1, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}


Subscriptions

Bookstackapp Bookstack
cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-15T19:04:50.041Z

Reserved: 2026-09-10T16:23:54.471Z

Link: CVE-2026-89022

cve-icon Vulnrichment

Updated: 2026-09-15T19:04:42.582Z

cve-icon NVD

Status : Received

Published: 2026-09-15T17:17:33.360

Modified: 2026-09-15T19:17:45.647

Link: CVE-2026-89022

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-15T18:30:14Z

Weaknesses
  • CWE-290

    Authentication Bypass by Spoofing