GitLab Community Edition/Enterprise Edition up to 18.7.4/18.8.4/18.9.0 redos

Summaryinfo

A vulnerability labeled as problematic has been found in GitLab Community Edition and Enterprise Edition up to 18.7.4/18.8.4/18.9.0. The impacted element is an unknown function. Such manipulation leads to redos. This vulnerability is uniquely identified as CVE-2026-1388. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in GitLab Community Edition and Enterprise Edition up to 18.7.4/18.8.4/18.9.0 and classified as problematic. Affected by this issue is an unknown part. The manipulation with an unknown input leads to a redos vulnerability. Using CWE to declare the problem leads to CWE-1333. The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. Impacted is availability. CVE summarizes:

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.

The weakness was disclosed by Sim4N6 as 587560. The advisory is available at gitlab.com. This vulnerability is handled as CVE-2026-1388 since 01/23/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1449.003 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 300132 (Linux Distros Unpatched Vulnerability : CVE-2026-1388), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 18.7.5, 18.8.5 or 18.9.1 eliminates this vulnerability. The upgrade is hosted for download at about.gitlab.com.

The vulnerability is also documented in the vulnerability database at Tenable (300132). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Bug Tracking Software

Vendor

• GitLab

Name

• Community Edition
• Enterprise Edition

Version

• 18.0
• 18.1
• 18.2
• 18.3
• 18.4
• 18.5
• 18.6
• 18.7
• 18.7.0
• 18.7.1
• 18.7.2
• 18.7.3
• 18.7.4
• 18.8
• 18.8.0
• 18.8.1
• 18.8.2
• 18.8.3
• 18.8.4
• 18.9.0

License

• open-source

Website

• Vendor: https://gitlab.com/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion