CVE-2025-12653: Authentication Bypass by Spoofing in GitLab

Published Nov 26, 2025
·
Updated

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.

Other sources

GitLab has remediated an issue that under specific conditions could have allowed an unauthenticated user to join arbitrary organizations by changing headers on some requests.

GitLab

Affected Software

7 affected componentsFixes available
GitLab GitLab>=18.3<18.4.5, >=18.5<18.5.3, >=18.6<18.6.1
18.4.518.5.318.6.1
GitLab GitLab>=18.3.0<18.4.5
GitLab GitLab>=18.3.0<18.4.5
GitLab GitLab>=18.5.0<18.5.3
GitLab GitLab>=18.5.0<18.5.3
GitLab GitLab=18.6.0
GitLab GitLab=18.6.0

Remediation

Information

Upgrade to versions 18.4.5, 18.5.3, 18.6.1 or above.

Event History

Nov 26, 2025
CVE Published
via MITRE·07:46 PM
Data Sourced
via MITRE·07:46 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·08:15 PM
DescriptionSeverityWeaknessAffected Software
Apr 21, 2026
Data Sourced
via GitLab·08:17 PM
DescriptionSeverityAffected Software

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2025-12653?

CVE-2025-12653 is a vulnerability that could allow unauthenticated users to join arbitrary organizations under specific conditions.

2

How do I fix CVE-2025-12653?

To patch CVE-2025-12653, upgrade your GitLab installation to version 18.4.5, 18.5.3, or 18.6.1.

3

What versions of GitLab are affected by CVE-2025-12653?

CVE-2025-12653 affects GitLab CE/EE versions prior to 18.4.5, 18.5.3, and 18.6.1.

4

Can CVE-2025-12653 impact user data security?

Yes, CVE-2025-12653 can potentially compromise user data security by allowing unauthorized access to organizations.

5

What should I do if I cannot update GitLab to fix CVE-2025-12653?

If an immediate update is not possible, consider implementing alternative security measures to restrict unauthorized access until the upgrade can be performed.

Contact

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