What is CVE-2021-39884?

CVE-2021-39884 is a medium-severity vulnerability in GitLab. CVSS score: 4.3/10. Published 2021-10-05.

How severe is CVE-2021-39884?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Vulnerability in GitLab

CVE-2021-39884

In all versions of GitLab EE since version 8.13, an endpoint discloses names of private groups that have access to a project to low privileged users that are part of that project.

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

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.010 (61.4th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 61st percentile — 61.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

GitLab — versions >=8.13, <14.1.7, >=14.2, <14.2.5, >=14.3, <14.3.1

References

gitlab.com/gitlab-org/gitlab/-/issues/25414 (Broken Link)
hackerone.com/reports/447817 (Permissions Required)
gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39884.json (Vendor Advisory)

Frequently asked questions

What is CVE-2021-39884?: CVE-2021-39884 is a medium-severity vulnerability in GitLab. CVSS score: 4.3/10. Published 2021-10-05.
How severe is CVE-2021-39884?: Medium severity. CVSS v3 base score is 4.3 out of 10.