CVE-2023-6678: Inefficient Regular Expression Complexity in GitLab

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-12 · updated 2026-06-17
Weakness: CWE-1333

Description

An issue has been discovered in GitLab EE affecting all versions before 16.8.6, all versions starting from 16.9 before 16.9.4, all versions starting from 16.10 before 16.10.2. It was possible for an attacker to cause a denial of service using malicious crafted content in a junit test report file.

Affected products

GitLab: before 16.8.6; from 16.9.0 before 16.9.4; from 16.10.0 before 16.10.2 — fixed in 16.10.2, 16.8.6, 16.9.4

How to fix

Upgrade to a fixed version: GitLab 16.10.2, 16.8.6, 16.9.4. Check the vendor advisory for mitigations.

References

https://gitlab.com/gitlab-org/gitlab/-/issues/434689
https://hackerone.com/reports/2268037
https://gitlab.com/gitlab-org/gitlab/-/issues/434689
https://hackerone.com/reports/2268037

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