CVE-2026-5309: Authorization Bypass Through User-Controlled Key in GitLab

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-25 · updated 2026-06-26
Weakness: CWE-639

Description

GitLab has remediated an issue in GitLab EE affecting all versions from 18.6 before 18.11.6, 19.0 before 19.0.3, and 19.1 before 19.1.1 that under certain conditions could have allowed an authenticated user to read or modify another group's virtual registry cleanup policy settings without authorization.

Affected products

GitLab: from 18.6.0 before 18.11.6; from 19.0.0 before 19.0.3; 19.1.0 — fixed in 18.11.6, 19.0.3

How to fix

Upgrade to a fixed version: GitLab 18.11.6, 19.0.3. Check the vendor advisory for mitigations.

References

https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-1-1-released/
https://gitlab.com/gitlab-org/gitlab/-/work_items/595468
https://hackerone.com/reports/3628793

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