Description
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 15.0 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1 that, when a merge request in a public project referenced a confidential issue from a private project, an authenticated user with no project membership could have read the confidential issue's title, due to a viewer-independent fragment cache key that incorrectly shared per-user-redacted rendered content across all users.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| GitLab | GitLab | 15.0 – < 19.3.6, 19.4 – < 19.4.3, 19.5 – < 19.5.1 | 19.3.6 |
Advisories 2
- WID-SEC-2026-4115 GitLab: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 9, 2026
- NCSC-2026-0447 Kwetsbaarheden verholpen in GitLab door GitLab Inc. NCSC-NL (Netherlands) · Oct 22, 2026
References
- https://gitlab.com/gitlab-org/gitlab/-/work_items/632207
- HackerOne Bug Bounty Report #3963293 technical-description exploit permissions-required
- https://docs.gitlab.com/releases/patches/patch-release-gitlab-19-5-1-released/