What is CVE-2026-5309?

CVE-2026-5309 is a medium-severity vulnerability in Gitlab, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.4/10. Published 2026-06-25.

How severe is CVE-2026-5309?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Auth bypass in Gitlab

CVE-2026-5309

GitLab has remediated an issue in GitLab EE affecting all versions from 18.6 before 18.11.6, 19.0 before 19.0.3, and 19.1 before 19.1.1 that under certain conditions could have allowed an authenticated user to read or modify another group'…

Vulnerability class: IDOR (Insecure Direct Object Reference)

EPSS: 0.002 (6.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Gitlab — versions 18.6, 19.0, 19.1

Weakness classification (CWE)

CWE-639 — Authorization Bypass Through User-Controlled Key

References

cve@gitlab.com
cve@gitlab.com
cve@gitlab.com (technical-description, permissions-required, exploit)

Frequently asked questions

What is CVE-2026-5309?: CVE-2026-5309 is a medium-severity vulnerability in Gitlab, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.4/10. Published 2026-06-25.
How severe is CVE-2026-5309?: Medium severity. CVSS v3 base score is 5.4 out of 10.