dbcve.org
GitLabApplication

CVE-2021-39912

MEDIUM · 5.3 CVSS v3.1 Published 2021-11-05
Fix available
A fix is available. Upgrade to 14.2.6 / 14.3.4 or later.
See remediation →
62/100
Remediation priority · Elevated
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
A potential DoS vulnerability was discovered in GitLab CE/EE starting with version 13.7. Using a malformed TIFF images was possible to trigger memory exhaustion.

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 · moderate confidence

A denial of service vulnerability exists in GitLab CE/EE versions 13.7 and later where processing a malformed TIFF image can trigger memory exhaustion, potentially causing the service to become unavailable.

MitigationUpdate GitLab to the patched version (contact GitLab for specific fixed version) or implement temporary image upload restrictions until patching is feasible.

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:>= 13.7.0, < 14.2.6>= 14.3.0, < 14.3.4>= 14.4.0, < 14.4.1

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
None
Integrity
None
Availability
Low

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

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. Determine your installed GitLab version
    Run 'gitlab-rake gitlab:env:info' or check '/opt/gitlab/VERSION' file, or view the version in the Admin Area > Dashboard in the web UI
    Affected if The installed version falls within any of these ranges: 13.7.0 to 14.2.5, 14.3.0 to 14.3.3, or 14.4.0
  2. Check if image uploads are enabled in project settings
    Navigate to a project's Settings > General > Visibility, project features, permissions or check via API: GET /projects/:id with include_settings=true
    Affected if File uploads or the markdown editor that processes images is enabled for projects where users can upload files
  3. Verify TIFF file processing is possible
    Attempt to upload a test TIFF file to an issue, merge request comment, or project wiki, or inspect gitlab-rails configuration for file type restrictions in /etc/gitlab/gitlab.rb (gitlab['default_project_features']['issues'] and associated upload settings)
    Affected if TIFF files can be uploaded and GitLab attempts to generate thumbnails or process image metadata for them
  4. Check if the file upload feature is exposed to unauthenticated or external users
    Review project and group visibility settings, and check if public or internal users can create issues/comments with attachments via API or web UI
    Affected if Users who can create issues, comments, or upload files are able to submit TIFF attachments without size or type restrictions

You are affected if your GitLab version is 13.7.0-14.2.5, 14.3.0-14.3.3, or 14.4.0 AND users can upload or attach malformed TIFF image files that GitLab processes.

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 14.2.6 / 14.3.4 / 14.4.1 or later
Fixed in 14.2.614.3.414.4.1
Interim mitigation

Update GitLab to the patched version (contact GitLab for specific fixed version) or implement temporary image upload restrictions until patching is feasible.

Recommended fix High confidence

14.2.6, 14.3.4, or 14.4.1 depending on your current branch (14.4.1 recommended for latest stable)

  1. 1. Identify current GitLab version by navigating to Admin Area > Overview > Dashboard or running `gitlab-rake gitlab:env:info`
  2. 2. Determine appropriate upgrade path based on current version: if running 13.7.0-14.2.5 upgrade to 14.2.6; if running 14.3.0-14.3.3 upgrade to 14.3.4; if running 14.4.0 upgrade to 14.4.1
  3. 3. Create a full backup of GitLab data using `gitlab-backup-create` or the omnibus backup command
  4. 4. Review GitLab upgrade documentation for your specific version jump
  5. 5. Test the upgrade in a staging environment first
  6. 6. Schedule maintenance window and stop GitLab services
  7. 7. Update GitLab packages via package manager (e.g., `apt-get update && apt-get install gitlab-ce` or `yum update gitlab-ce`)
  8. 8. Reconfigure GitLab with `gitlab-ctl reconfigure`
Caveat Minor/patch upgrades within 14.x should have minimal breaking changes, but always review release notes before upgrading

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

Fix this in GitLab Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-39912 — 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-2021-39912 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