CVE-2021-4191

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 80.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2022-03-28 · updated 2026-06-17

Description

An issue has been discovered in GitLab CE/EE affecting versions 13.0 to 14.6.5, 14.7 to 14.7.4, and 14.8 to 14.8.2. Private GitLab instances with restricted sign-ups may be vulnerable to user enumeration to unauthenticated users through the GraphQL API.

Affected products

GitLab: from 13.0.0 before 14.6.5; from 14.7.0 before 14.7.4; from 14.8 before 14.8.2 — fixed in 14.6.5, 14.7.4, 14.8.2

How to fix

Upgrade to a fixed version: GitLab 14.6.5, 14.7.4, 14.8.2. Check the vendor advisory for mitigations.

References

https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-4191.json
https://gitlab.com/gitlab-org/gitlab/-/issues/343898
https://hackerone.com/reports/1089609
https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-4191.json
https://gitlab.com/gitlab-org/gitlab/-/issues/343898
https://hackerone.com/reports/1089609

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