Description
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.3 before 18.4.5, 18.5 before 18.5.3, and 18.6 before 18.6.1 that under specific conditions could have allowed an unauthenticated user to join arbitrary organizations by changing headers on some requests.
References (3)
Core 3
Core References
Release Notes vendor-advisory
https://about.gitlab.com/releases/2025/11/26/patch-release-gitlab-18-6-1-released/
Broken Link issue-tracking
permissions-required
https://gitlab.com/gitlab-org/gitlab/-/issues/579372
Permissions Required technical-description
exploit
permissions-required
https://hackerone.com/reports/3370245
Scores
CVSS v3
6.5
EPSS
0.0025
EPSS Percentile
15.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-290
Status
published
Products (2)
gitlab/gitlab
18.6.0 (2 CPE variants)
gitlab/gitlab
18.3.0 - 18.4.5 (2 CPE variants)
Published
Nov 26, 2025
Tracked Since
Feb 18, 2026