Vulnerability · Published Nov 26, 2025 · Assigned by GitLab
CVE-2025-12653Authentication Bypass by Spoofing in GitLab
Medium 6.5
In plain English
A medium-severity authentication bypass by spoofing in GitLab from GitLab. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 24% of all known vulnerabilities).
Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.3%top 76.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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.
Affected products (as reported)
Weakness: CWE-290 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
References
- GitLab Security Release Blog Post vendor-advisory
- GitLab Issue #579372 issue-tracking, permissions-required
- HackerOne Bug Bounty Report #3370245 technical-description, exploit, permissions-required