CVE-2026-16255

medium

Description

GitLab has remediated an issue in GitLab EE affecting all versions from 12.0 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1 that, 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.

References

https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-5-1-released/

https://hackerone.com/reports/3809350

https://gitlab.com/gitlab-org/gitlab/-/work_items/606479

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-107676

Details

Source: Mitre, NVD

Published: 2026-10-22

Updated: 2026-10-22

Risk Information

CVSS v2

Base Score: 5.6

Vector: CVSS2#AV:N/AC:H/Au:S/C:C/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 5.9

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:N

Severity: Medium

EPSS

EPSS: 0.00209