CVE-2026-1388

HIGH severity · CVSS 7.5 · CWE-1333

7.5CVSS HIGH

Summary

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 9.2 before 18.7.5, 18.8 before 18.8.5, and 18.9 before 18.9.1 that could have allowed an unauthenticated user to cause regular expression denial of service by sending specially crafted input to a merge request endpoint under certain conditions.

Impact & exploitability

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

Confidentiality impactNone

Integrity impactNone

Availability impactHigh

Exploit probability (EPSS)0%

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products we track (1)

GitLab

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Additional information

NVD record
https://about.gitlab.com/releases/2026/02/25/patch-release-gitlab-18-9-1-released/Advisory
https://gitlab.com/gitlab-org/gitlab/-/issues/587560
https://hackerone.com/reports/3482893