What is CVE-2021-39893?

CVE-2021-39893 is a medium-severity vulnerability in GitLab, classified under Missing Authorization. CVSS score: 5.3/10. Published 2021-10-05.

How severe is CVE-2021-39893?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in GitLab

CVE-2021-39893

A potential DOS vulnerability was discovered in GitLab starting with version 9.1 that allowed parsing files without authorisation.

Vulnerability class: Broken Access Control

Published 2021-10-05 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.011 (65.1th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 65th percentile — 65.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

GitLab — versions >=9.1, <14.1.7, >=14.2, <14.2.5, >=14.3, <14.3.1

Weakness classification (CWE)

CWE-862 — Missing Authorization

References

gitlab.com/gitlab-org/gitlab/-/issues/340076 (Broken Link)
gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39893.json (Vendor Advisory)

Frequently asked questions

What is CVE-2021-39893?: CVE-2021-39893 is a medium-severity vulnerability in GitLab, classified under Missing Authorization. CVSS score: 5.3/10. Published 2021-10-05.
How severe is CVE-2021-39893?: Medium severity. CVSS v3 base score is 5.3 out of 10.