CVE-2021-39931

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-12-13 · updated 2026-06-17

Description

An issue has been discovered in GitLab CE/EE affecting all versions starting from 8.11 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2. Under specific condition an unauthorised project member was allowed to delete a protected branches due to a business logic error.

Affected products

GitLab: from 8.11.0 before 14.3.6; from 14.4.0 before 14.4.4; from 14.5.0 before 14.5.2 — fixed in 14.3.6, 14.4.4, 14.5.2

How to fix

Upgrade to a fixed version: GitLab 14.3.6, 14.4.4, 14.5.2. Check the vendor advisory for mitigations.

References

https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39931.json
https://gitlab.com/gitlab-org/gitlab/-/issues/340445
https://hackerone.com/reports/1318379
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39931.json
https://gitlab.com/gitlab-org/gitlab/-/issues/340445
https://hackerone.com/reports/1318379

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