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TI-2026-60332 Aliases CVE-2026-89022GHSA-54r8-f2jx-5qj6

BookStack < 26.05.5 Authentication Bypass via Social Login Provider Confusion

Priority MEDIUM 42CWE-290Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-290.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00465 40th percentileScored 2026-11-07
Fix Fixed bookstack (bookstackapp): 26.05.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
bookstackappbookstackbefore 26.05.526.05.5Patch availableCNA
  • bookstack Vendorbookstackapp Affected before 26.05.5 Fixed in 26.05.5 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:bookstackapp:bookstack:*:*:*:*:*:*:*:*——bookstackapp
  • cpe:2.3:a:bookstackapp:bookstack:*:*:*:*:*:*:*:* Versions — — ·bookstackapp

Remediation

  • Fix · CNA bookstack (bookstackapp) Fixed in 26.05.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-89022
  2. 2026-10-03 Alias added: GHSA-54r8-f2jx-5qj6

References

Advisory 1

  • TI-2026-04803 BookStackApp BookStack Chapter Export ExportFormatter.php chapterToMarkdown access control CVSS 4.0MEDIUM 6.9
  • TI-2021-02995 Improper Access Control in bookstackapp/bookstack CVSS 3.1CRITICAL 9.8
  • TI-2023-04263 Server-Side Request Forgery (SSRF) in bookstackapp/bookstack CVSS 3.1LOW 2.4
  • TI-2026-56847 BookStack before 26.05.4 Remote Code Execution via Book Cover CVSS 4.0HIGH 8.7
  • TI-2020-04312 Remote Code Execution Through Image Uploads in BookStack CVSS 3.1HIGH 8.8
  • TI-2026-58223 BookStack before 26.05.4 Stored XSS via Drawing Upload CVSS 4.0CRITICAL 9.3
See all 26 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences