---
id: "CVE-2021-39935"
kind: "vulnerability"
aliases: ["CVE-2021-39935"]
title: "An issue has been discovered in GitLab CE/EE affecting all versions starting from 10.5 before 14.3.6, all versions\u2026"
severity: "high"
cvss: 7.5
epss: null
exploited: true
status: "open"
category: "package"
products: [{"name": "GitLab Community and Enterprise Editions", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "gitlab", "fixed": ["14.3.6"], "affected": ">= 10.5.0, < 14.3.6", "ecosystem": "vendor"}, {"name": "gitlab", "fixed": ["14.4.4"], "affected": ">= 14.4.0, < 14.4.4", "ecosystem": "vendor"}, {"name": "gitlab", "fixed": ["14.5.2"], "affected": ">= 14.5.0, < 14.5.2", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "gitlab", "package", "self-hosted"]
not_affected_if: ["managed-hosting"]
published_at: "2021-12-13T16:15:09+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T23:44:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-39935", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-39935", "first_seen_at": "2026-10-23T23:44:51+00:00"}]
---

# An issue has been discovered in GitLab CE/EE affecting all versions starting from 10.5 before 14.3.6, all versions…

GitLab Community and Enterprise Editions have a server-side request forgery flaw in the CI Lint API. An unauthenticated external attacker can make the GitLab server send requests to internal or external destinations of their choosing.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:GitLab Community and Enterprise Editions affected ? fixed ?
- vendor:gitlab affected >= 10.5.0, < 14.3.6 fixed 14.3.6
- vendor:gitlab affected >= 14.4.0, < 14.4.4 fixed 14.4.4
- vendor:gitlab affected >= 14.5.0, < 14.5.2 fixed 14.5.2

## Fix

Apply the mitigations and upgrade to the fixed GitLab version per vendor instructions; the sources do not name the fixed version.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-39935
- 2026-10-23T23:44:51+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2021-39935

## From the sources

GitLab Community and Enterprise Editions contain a server-side request forgery vulnerability which could allow unauthorized external users to perform Server Side Requests via the CI Lint API.

CISA 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.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_