Vulnerability Description
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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Gitlab | Gitlab | >= 9.2.0, < 18.7.5 |
Related Weaknesses (CWE)
References
- https://about.gitlab.com/releases/2026/02/25/patch-release-gitlab-18-9-1-releaseRelease NotesVendor Advisory
- https://gitlab.com/gitlab-org/gitlab/-/issues/587560Broken Link
- https://hackerone.com/reports/3482893Permissions Required
FAQ
What is CVE-2026-1388?
CVE-2026-1388 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 regula...
How severe is CVE-2026-1388?
CVE-2026-1388 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-1388?
Check the references section above for vendor advisories and patch information. Affected products include: Gitlab Gitlab.