Description
An issue has been discovered in GitLab CE/EE affecting all versions from 16.11 before 18.1.6, 18.2 before 18.2.6, and 18.3 before 18.3.2 that could have allowed authenticated users to make unintended internal requests through proxy environments by injecting crafted sequences.
Affected products
gitlab: gitlab
References3
- about.gitlab.com/releases/2025/09/10/patch-release-gitlab-18-3-… Release NotesVendor Advisory
- gitlab.com/gitlab-org/gitlab/-/issues/550766 Broken Link
- hackerone.com/reports/3162711 Permissions Required
Metrics
- CVSS 3.1
-
8.8
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 55 · as of 8 November 2026
- CWE
- CWE-918
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.