Description
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 15.11 before 18.4.6, 18.5 before 18.5.4, and 18.6 before 18.6.2 that could have, under certain circumstances, allowed an unauthenticated user to perform unauthorized actions on behalf of another user by injecting malicious external scripts into the Swagger UI."
Affected products
gitlab: gitlab
References3
- about.gitlab.com/releases/2025/12/10/patch-release-gitlab-18-6-… Release NotesVendor Advisory
- gitlab.com/gitlab-org/gitlab/-/issues/577975 Broken Link
- hackerone.com/reports/3317485 Permissions Required
Metrics
- CVSS 3.1
-
8.0
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N - EPSS — exploit probability
- 1% percentile: 46 · as of 11 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.