dbcve.org
GitLabApplication

CVE-2021-4191

MEDIUM · 5.3 CVSS v3.1 Published 2022-03-28
Fix available
A fix is available. Upgrade to 14.6.5 / 14.7.4 or later.
See remediation →
62/100
Remediation priority · Elevated
High EPSS Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The GitLab GraphQL API in versions 13.0 through 14.8.2 allows unauthenticated user enumeration on private instances with restricted sign-ups. Attackers can query the GraphQL endpoint to discover valid usernames, potentially facilitating brute-force attacks or reconnaissance.

MitigationUpgrade GitLab to version 14.9.0, 14.8.5, 14.7.5, or 14.6.6 or later. Alternatively, restrict unauthenticated access to the GraphQL API endpoint at the load balancer or firewall level.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
GitLabApplication
Affected:>= 13.0.0, < 14.6.5>= 14.7.0, < 14.7.4>= 14.8, < 14.8.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check your GitLab version
    Run 'gitlab-rake gitlab:env:info' or check the GitLab admin area under /admin/application_settings or look at /opt/gitlab/embedded/service/gitlab-rails/VERSION file
    Affected if The installed version falls within these ranges: >= 13.0.0 and < 14.6.5; >= 14.7.0 and < 14.7.4; >= 14.8.0 and < 14.8.2
  2. Verify GraphQL endpoint accessibility
    Attempt to access the GraphQL endpoint at /api/graphql without providing authentication credentials. Check your load balancer, firewall, or GitLab configuration for any rules allowing unauthenticated access to the /api/graphql path.
    Affected if The GraphQL API endpoint responds to unauthenticated requests (returns data instead of a 401/302 redirect to login)
  3. Confirm sign-up restrictions are in place
    Check GitLab admin settings under /admin/application_settings/general or inspect the 'gitlab.rb' configuration file for 'gitlab_rails['gitlab_signup_enabled']' setting
    Affected if User sign-ups are disabled or restricted (gitlab_signup_enabled is set to false), which is the condition described in the CVE that makes enumeration useful for attackers

You are affected if your GitLab version is in the vulnerable range AND the GraphQL endpoint is accessible to unauthenticated users, especially on instances with restricted sign-ups.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 14.6.5 / 14.7.4 / 14.8.2 or later
Fixed in 14.6.514.7.414.8.2
Interim mitigation

Upgrade GitLab to version 14.9.0, 14.8.5, 14.7.5, or 14.6.6 or later. Alternatively, restrict unauthenticated access to the GraphQL API endpoint at the load balancer or firewall level.

Recommended fix High confidence

GitLab 14.8.2 or later (alternatively 14.7.4 or 14.6.5)

  1. Back up your GitLab instance database and configuration before upgrading
  2. Ensure you have adequate downtime window for the upgrade process
  3. For Omnibus installations: Run 'gitlab-ctl stop' to stop GitLab services
  4. Upgrade GitLab to version 14.8.2 or later (14.7.4 or 14.6.5 are also fixed but earlier in their respective branches)
  5. For Omnibus: Run 'gitlab-ctl start' or 'gitlab-ctl restart' after upgrade completes
  6. Verify the GraphQL API no longer allows unauthenticated user enumeration
  7. Confirm users cannot query user information without authentication
Caveat Standard upgrade risks apply - review GitLab release notes for deprecations and ensure compatibility with your runners and integrated tools

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in GitLab Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-4191 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-4191 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data