How severe is CVE-2021-39935?

CVE-2021-39935 has a CVSS 3.1 base score of 6.8 (MEDIUM). EPSS estimates a 35.6% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-39935: GitLab Community and Enterprise Editions Server-Side

CISA Known Exploited Vulnerabilities

GitLab Community and Enterprise Editions Server-Side Request Forgery (SSRF) Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2026-02-03

Remediation due

2026-02-24

Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

CISA notes
https://about.gitlab.com/releases/2021/12/06/security-release-gitlab-14-5-2-released/ ; https://nvd.nist.gov/vuln/detail/CVE-2021-39935

Description

An issue has been discovered in GitLab CE/EE affecting all versions starting from 10.5 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2. Unauthorized external users could perform Server Side Requests via the CI Lint API

Severity

CVSS 3.1 · CNA6.8 MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impactpartial

Affected Products

Vendor	Product	Affected versions
GitLab	GitLab	>=10.5, <14.3.6 >=14.4, <14.4.4 >=14.5, <14.5.2

References

3 Links

Other references

Record Details

Published

2021-12-13

Last updated

2026-02-03

Assigner (CNA)

GitLab

Credited to

Thanks @minhli for reporting this vulnerability through our HackerOne bug bounty program

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.