What is CVE-2026-12910?

CVE-2026-12910 is a medium-severity vulnerability in GitLab, classified under Missing Authentication for Critical Function. CVSS score: 5.4/10. Published 2026-09-15.

How severe is CVE-2026-12910?

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

Auth bypass in GitLab

CVE-2026-12910

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.6 before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2 that under certain conditions could have allowed an authenticated user to bypass SAML SSO sign-in restrictions and authenticate without SSO due to missing authentication enforcement checks.

Vulnerability class: Broken Authentication

Published 2026-09-15 · last modified 2026-09-28.

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.

EPSS exploit prediction

EPSS: 0.003 (27.4th percentile), scored 2026-10-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.4% 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: 0.003 · change: +0.002

Affected products

GitLab

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

References

gitlab.com/gitlab-org/gitlab/-/work_items/603742 (Broken Link)
hackerone.com/reports/3745561 (Permissions Required, technical-description, permissions-required, exploit)

Frequently asked questions

What is CVE-2026-12910?: CVE-2026-12910 is a medium-severity vulnerability in GitLab, classified under Missing Authentication for Critical Function. CVSS score: 5.4/10. Published 2026-09-15.
How severe is CVE-2026-12910?: Medium severity. CVSS v3 base score is 5.4 out of 10.