XSS in GitLab
CVE-2026-5262
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 16.1.0 before 18.9.6, 18.10 before 18.10.4, and 18.11 before 18.11.1 that under certain conditions could have allowed an unauthenticated user to access tokens in the Storybook development environment due to improper input validation.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.004 (26.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 26.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.004 · change: +0.001
Affected products
- GitLab — versions 18.10, 18.11, 18.11.0
Weakness classification (CWE)
References
- gitlab.com/gitlab-org/gitlab/-/work_items/595332 (Broken Link)
- hackerone.com/reports/3574642 (Permissions Required, technical-description, permissions-required, exploit)
- about.gitlab.com/releases/2026/04/22/patch-release-gitlab-18-11-1-released/ (Release Notes, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-5262?
- CVE-2026-5262 is a high-severity vulnerability in GitLab, classified under Cross-site Scripting. CVSS score: 8.0/10. Published 2026-04-22.
- How severe is CVE-2026-5262?
- High severity. CVSS v3 base score is 8.0 out of 10.