CVE-2026-1388
ReDoS Vulnerability in GitLab Merge Request Endpoint
Publication date: 2026-02-25
Last updated on: 2026-02-28
Assigner: GitLab Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| gitlab | gitlab | From 18.8.0 (inc) to 18.8.5 (exc) |
| gitlab | gitlab | From 18.8.0 (inc) to 18.8.5 (exc) |
| gitlab | gitlab | 18.9.0 |
| gitlab | gitlab | 18.9.0 |
| gitlab | gitlab | From 9.2.0 (inc) to 18.7.5 (exc) |
| gitlab | gitlab | From 9.2.0 (inc) to 18.7.5 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-1333 | The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. |
Attack-Flow Graph
AI Powered Q&A
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade GitLab CE/EE to a fixed version. Specifically, update to version 18.7.5 or later if you are using the 18.7 series, 18.8.5 or later for the 18.8 series, or 18.9.1 or later for the 18.9 series.
This vulnerability allows an unauthenticated user to cause a denial of service via specially crafted input to a merge request endpoint, so applying the patch by upgrading is the recommended immediate action.
Can you explain this vulnerability to me?
This vulnerability in GitLab CE/EE affects versions from 9.2 before 18.7.5, 18.8 before 18.8.5, and 18.9 before 18.9.1. It allows an unauthenticated user to cause a regular expression denial of service (ReDoS) by sending specially crafted input to a merge request endpoint under certain conditions.
How can this vulnerability impact me? :
The impact of this vulnerability is a denial of service (DoS) condition. An attacker can cause the GitLab service to become unavailable or unresponsive by exploiting the regular expression processing in the merge request endpoint, potentially disrupting normal operations.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know