CVE-2023-3909

Public Exploit
Inefficient Regular Expression Complexity in GitLab

Description

An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.3 before 16.3.6, all versions starting from 16.4 before 16.4.2, all versions starting from 16.5 before 16.5.1. A Regular Expression Denial of Service was possible by adding a large string in timeout input in gitlab-ci.yml file.

Remediation

Solution:

  • Upgrade to version 16.5.1, 16.4.2, 16.3.6

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.14%
Affected: GitLab GitLab
Published at:
Updated at:

References

Link Tags
https://gitlab.com/gitlab-org/gitlab/-/issues/418763 issue tracking broken link permissions required
https://hackerone.com/reports/2050269 broken link exploit permissions required technical description

Frequently Asked Questions

What is the severity of CVE-2023-3909?
CVE-2023-3909 has been scored as a medium severity vulnerability.
How to fix CVE-2023-3909?
To fix CVE-2023-3909: Upgrade to version 16.5.1, 16.4.2, 16.3.6
Is CVE-2023-3909 being actively exploited in the wild?
It is possible that CVE-2023-3909 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-3909?
CVE-2023-3909 affects GitLab GitLab.
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