CVE-2023-3909: Parsing gitlab-ci.yml with large string via timeout input leads to Denial of Service

Published Oct 31, 2023
·
Updated

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.

Affected Software

7 affected componentsFixes available
GitLab GitLab>=12.3.0<16.3.6
GitLab GitLab>=12.3.0<16.3.6
GitLab GitLab>=16.4.0<16.4.2
GitLab GitLab>=16.4.0<16.4.2
GitLab GitLab=16.5.0
GitLab GitLab=16.5.0
GitLab GitLab>=12.3<16.3.6, >=16.4<16.4.2, >=16.5<16.5.1
16.3.616.4.216.5.1

Remediation

Information

Upgrade to version 16.5.1, 16.4.2, 16.3.6

Event History

Nov 6, 2023
CVE Published
via MITRE·12:08 PM
Data Sourced
via MITRE·12:08 PM
RemedyDescriptionSeverityWeakness
Apr 22, 2026
Data Sourced
via GitLab·08:52 AM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is CVE-2023-3909?

CVE-2023-3909 is a vulnerability in GitLab that allows for uncontrolled resource consumption.

2

Which versions of GitLab are affected by CVE-2023-3909?

All versions starting from 12.3 before 16.3.6, all versions starting from 16.4 before 16.4.2, and version 16.5.0 are affected by CVE-2023-3909.

3

What is the severity of CVE-2023-3909?

CVE-2023-3909 has a severity value of 6.5, which is considered medium.

4

How can I fix CVE-2023-3909?

To fix CVE-2023-3909, update GitLab to version 16.3.6, 16.4.2, or 16.5.1.

5

Where can I find more information about CVE-2023-3909?

You can find more information about CVE-2023-3909 on the GitLab issue page (https://gitlab.com/gitlab-org/gitlab/-/issues/418763) and the HackerOne report (https://hackerone.com/reports/2050269).

Contact

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