High

Analysis Summary

GitLab has released urgent security patches for both its Community (CE) and Enterprise (EE) editions, addressing six vulnerabilities that pose serious risks to self-managed instances. Among these, two are classified as high-severity flaws capable of enabling Server-Side Request Forgery (SSRF) and Denial of Service (DoS) attacks. The affected versions span from 7.12 to the most recent releases, underscoring the wide impact of these vulnerabilities. Administrators of self-managed GitLab environments are strongly advised to upgrade immediately to versions 18.3.2, 18.2.6, or 18.1.6. Users of GitLab’s cloud-hosted service (GitLab.com) and GitLab Dedicated are already protected and do not need to take further action.

The most critical issue fixed in this patch cycle is the SSRF vulnerability, tracked as CVE-2025-6454, with a CVSS score of high. Found in the Webhook custom header feature, it could be exploited by authenticated attackers to force GitLab instances into making unauthorized internal requests, potentially leading to lateral movement or further compromise. This flaw affected all versions starting from 16.11. The second high-severity flaw, CVE-2025-2256, is a DoS vulnerability with a CVSS score of 7.5. It allowed unauthenticated attackers to overwhelm GitLab instances by flooding them with concurrent SAML responses, rendering the platform inaccessible to legitimate users.

In addition to these, GitLab addressed four medium-severity vulnerabilities, three of which also resulted in denial-of-service scenarios. These include CVE-2025-1250, where crafted commit messages or merge request descriptions could stall background job processing; CVE-2025-7337, which allowed Developer-level users to crash an instance through large file uploads; and CVE-2025-10094, enabling disruption of token-related operations through excessively long token names. Another flaw, CVE-2025-6769, with a lower CVSS score of 4.3, involved unauthorized access to administrator-only maintenance notes through runner details, leading to potential information disclosure.

The vulnerabilities were responsibly disclosed through GitLab’s HackerOne bug bounty program, with recognition given to researchers including yuki_osaki, ppee, pwnie, and iamgk808. Consistent with its disclosure policy, GitLab will publish the full technical details of these issues on its issue tracker 30 days after the patch release. The company has reiterated the importance of applying these patches promptly, as the flaws present opportunities for attackers to disrupt operations or gain access to sensitive environments if left unaddressed.

Impact

• Denial of Service
• Gain Access

Indicators of Compromise

CVE

• CVE-2025-1250

• CVE-2025-7337

• CVE-2025-10094

• CVE-2025-6769

Affected Vendors

Remediation

• Update self-managed GitLab installations to the latest patched versions: 18.3.2, 18.2.6, or 18.1.6.
• Ensure both Community Edition (CE) and Enterprise Edition (EE) instances are patched.
• No action is required for GitLab.com (cloud-hosted) and GitLab Dedicated users as they are already protected.
• Restrict access to GitLab instances to trusted networks and enforce strong authentication controls.
• Monitor and log activity for abnormal webhook usage or excessive SAML responses.
• Review and validate commit messages, merge requests, and token creation to prevent abuse.
• Limit file upload sizes to prevent resource exhaustion.
• Regularly audit user permissions, ensuring only trusted users have Developer-level or higher access.
• Monitor background job processing for potential stalling or unusual activity.
• Review GitLab’s official security announcement for any additional mitigations.
• Stay updated on GitLab’s issue tracker, as full vulnerability details will be disclosed after 30 days.
• Continue to apply GitLab’s scheduled patch releases promptly to minimize exposure.