Description
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 15.6 before 18.4.6, 18.5 before 18.5.4, and 18.6 before 18.6.2 that could have allowed an authenticated user to, under certain conditions, render content in dialogs to other users by injecting malicious HTML content into merge request titles.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| GitLab | GitLab | 15.6 – < 18.4.6, 18.5 – < 18.5.4, 18.6 – < 18.6.2 | 18.4.6 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | gitlab | No fix yet | — |
Advisories 2
- WID-SEC-2025-2822 GitLab: Mehrere Schwachstellen BSI CERT-Bund (WID) · Dec 11, 2025
- NCSC-2025-0390 Kwetsbaarheden verholpen in GitLab CE/EE NCSC-NL (Netherlands) · Dec 11, 2025
References
- GitLab Issue #579573 issue-tracking permissions-required
- HackerOne Bug Bounty Report #3379381 technical-description exploit permissions-required
- https://about.gitlab.com/releases/2025/12/10/patch-release-gitlab-18-6-2-released/