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Open-source package vulnerability · GitLab

CVE-2026-16255: GitLab EE incomplete enforcement of instance-wide SAML/LDAP membership lock

mediumCVSS 3.1 5.9

When the instance-wide SAML or LDAP membership lock was enabled, an authenticated user could have granted or accepted project and group membership outside the identity provider's control, due to incomplete enforcement of the membership lock on requests created before the lock was enabled. Impacted versions: GitLab EE all versions from 12.0 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1.

Published Oct 21, 2026

Advisory details

From the National Vulnerability Database. This product uses the NVD API but is not endorsed or certified by the NVD.

When the instance-wide SAML or LDAP membership lock was enabled, an authenticated user could have granted or accepted project and group membership outside the identity provider's control, due to incomplete enforcement of the membership lock on requests created before the lock was enabled. Impacted versions: GitLab EE all versions from 12.0 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1. Fixed in GitLab CE/EE 19.5.1, 19.4.3 and 19.3.6, released October 21, 2026.

Credited to 3nvz.

References

How this page is made: the data panel comes from the GitHub Advisory Database, CISA’s KEV catalog, the NVD and FIRST EPSS, and updates twice a day. No analysis has been written for this entry yet. Methodology

Coverage on the Beam blog

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