Description
An issue has been discovered in GitLab CE/EE affecting all versions from 7.0 before 18.11.13, 19.0 before 19.0.10, 19.1 before 19.1.9, 19.2 before 19.2.9, 19.3 before 19.3.6, 19.4 before 19.4.3, and 19.5 before 19.5.1 that, under certain conditions, could have allowed an unauthenticated user to execute arbitrary code on the GitLab server due to integer overflow when compiling a specially crafted regular expression.
Affected products
gitlab: gitlab
References4
- docs.gitlab.com/releases/patches/patch-release-gitlab-19-5-1-re… Release NotesVendor Advisory
- gitlab.com/gitlab-org/gitlab/-/work_items/633633 Permissions Required
- hackerone.com/reports/4093475 Permissions Required
- www.ruby-lang.org/en/news/2026/10/23/regexp-fixes-for-gitlab-cv…
Metrics
- CVSS 3.1
-
10.0
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 72 · as of 8 November 2026
- CWE
- CWE-190
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.