CVE intelligence and bounded remediation

CVE-2021-39927 — Gitlab Gitlab security vulnerability

Medium CVSS 4.3

Server side request forgery protections in GitLab CE/EE versions between 8.4 and 14.4.4, between 14.5.0 and 14.5.2, and between 14.6.0 and 14.6.1 would fail to protect against attacks sending requests to localhost on port 80 or 443 if GitLab was configured to run on a port other than 80 or 443

Severity
Medium
CVSS
4.3 (3.1)
Published
2022-01-18
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-918

Affected products

  • gitlab / gitlab

Showing 1 representative product identities from 6 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Server-side request forgery and unintended proxying

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Inventory server-side URL fetchers, webhooks, importers, previews, redirects, proxies, and protocol handlers reachable from untrusted input.
  • Map egress paths to internal services, metadata endpoints, loopback, private address space, and privileged control planes.
  • Review DNS resolution, redirect, proxy, credential-forwarding, and URL parsing behavior without requesting sensitive targets.

Remediate safely

  • Replace arbitrary destinations with named integrations or a strict allowlist of schemes, hosts, ports, and paths.
  • Resolve and validate every destination and redirect hop, then enforce egress policy independently of application checks.
  • Remove ambient credentials and sensitive headers from fetchers; apply response size, time, and content limits.

Authoritative sources

Complete CVE record and remediation plan

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