CVE-2025-12653

Authentication Bypass by Spoofing in GitLab

State: Published
Severity: 6.5 Medium
Published: Nov 26, 2025
Updated: Dec 10, 2025
Reserved: Nov 3, 2025

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.

Scores

CVSS	Score	Vector	Source
3.1	6.5 Medium	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N	GitLab

Weaknesses

CWE-290 Authentication Bypass by Spoofing

Affected Products

Product	Versions
GitLabGitLab	18.3 to before 18.4.5Affected 18.5 to before 18.5.3Affected 18.6 to before 18.6.1Affected

References

GitLab Security Release Blog Postvendor-advisory
GitLab Issue #579372issue-trackingpermissions-required
HackerOne Bug Bounty Report #3370245technical-descriptionexploitpermissions-required

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.