CVE-2023-3909

Name: CVE-2023-3909
Creator: NVD / NIST
Published: 2023-11-06T13:15:09.653+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.60%

Last modified Jun 17, 2026

CVE-2023-3909 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. 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.. EPSS estimates a 0.60% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.60%

43.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Gitlab	Gitlab	>= 12.3.0, < 16.3.6
Gitlab	Gitlab	>= 16.4.0, < 16.4.2
Gitlab	Gitlab	16.5.0

References

https://gitlab.com/gitlab-org/gitlab/-/issues/418763Broken Link
https://hackerone.com/reports/2050269Permissions Required
https://gitlab.com/gitlab-org/gitlab/-/issues/418763Broken Link
https://hackerone.com/reports/2050269Permissions Required

Timeline

Published: Nov 6, 2023
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2023-3909?

How severe is CVE-2023-3909?

CVE-2023-3909 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.60% probability of exploitation in the next 30 days.

How do I fix CVE-2023-3909?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-3909?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST