CVE-2026-89022 BookStack - Authentication Bypass

BookStack < 26.05.5 contains an authentication bypass caused by improper validation in social login implementation, letting unauthenticated attackers sign in as arbitrary users by exploiting driver_id namespace collision, exploit requires enabled social login providers.

CVSS base score 7.4 /10
High
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.46% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Authentication Bypass
Impact
Broken Authentication
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Published
15 September 2026
Updated
15 October 2026
Weakness
CWE-290

Vendor fix

Update to version 26.05.5 or later.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

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