CVE-2026-56774: Kanboard - Cross-User Deletion of Persistent Login Sessions via Unvalidated Session ID

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-25 · updated 2026-07-14
Weakness: CWE-639

Description

Kanboard through 1.2.52, fixed in commit 928c68a, UserViewController::removeSession fails to validate the session id parameter before passing it to RememberMeSessionModel::remove, allowing authenticated users to delete other users' Remember Me sessions. Attackers can enumerate sequential session IDs and mass-invalidate persistent login sessions of any user, including administrators, forcing re-authentication and causing denial of service.

Affected products

kanboard: through 1.2.52

References

https://github.com/kanboard/kanboard/commit/928c68aa2b7c00092dd71084d329b912e229f3d1
https://github.com/kanboard/kanboard/issues/5829
https://github.com/kanboard/kanboard/pull/5831
https://www.vulncheck.com/advisories/kanboard-cross-user-deletion-of-persistent-login-sessions-via-unvalidated-session-id

Get alerted when CVE-2026-56774 or the next vulnerability affects your stack