dbcve.org
GitLabApplication

CVE-2026-1659

HIGH · 7.5 CVSS v3.1 Published 2026-05-14
Fix available
A fix is available. Upgrade to 18.9.7 / 18.10.6 or later.
See remediation →
84/100
Remediation priority · High
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
GitLab has remediated an issue in GitLab CE/EE affecting all versions from 9.0 before 18.9.7, 18.10 before 18.10.6, and 18.11 before 18.11.3 that could have allowed an unauthenticated user to cause denial of service by sending specially crafted requests due to insufficient input validation.

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

GitLab CE/EE versions 9.0 through 18.11.2 contained an input validation vulnerability that allowed unauthenticated attackers to cause denial of service via specially crafted HTTP requests. The insufficient input validation allowed malicious requests to consume excessive server resources.

MitigationUpgrade GitLab to version 18.9.7, 18.10.6, 18.11.3 or later to remediate this vulnerability. Implement rate limiting at the network perimeter as an interim compensating control.

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:>= 9.0.0, < 18.9.7>= 18.10.0, < 18.10.6>= 18.11.0, < 18.11.3

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
High

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

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 GitLab version via command line
    Run `gitlab-rake gitlab:env:info` or check `/opt/gitlab/version` on the GitLab server. Alternatively, look at the footer of any GitLab page or navigate to Admin Area > Settings > General to view the version.
    Affected if The displayed version falls within any of these ranges: 9.0.0 to 18.9.6, 18.10.0 to 18.10.5, or 18.11.0 to 18.11.2
  2. Check GitLab version via package manager
    If installed via omnibus, run `gitlab-ctl version` or check the installed package with `dpkg -l | grep gitlab` (Debian/Ubuntu) or `rpm -qa | grep gitlab` (RHEL/CentOS).
    Affected if The package version matches any of the affected ranges listed above
  3. Verify GitLab web service is exposed
    Confirm the GitLab instance is reachable via HTTP/HTTPS. This vulnerability is exploitable via specially crafted HTTP requests to any publicly accessible endpoint.
    Affected if The GitLab web interface is accessible over the network (no additional configuration needs to be enabled for this vulnerability to apply)

A user is affected if their GitLab installation version is 9.0.0 through 18.9.6, 18.10.0 through 18.10.5, or 18.11.0 through 18.11.2 and the service is network-accessible.

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 18.9.7 / 18.10.6 / 18.11.3 or later
Fixed in 18.9.718.10.618.11.3
Interim mitigation

Upgrade GitLab to version 18.9.7, 18.10.6, 18.11.3 or later to remediate this vulnerability. Implement rate limiting at the network perimeter as an interim compensating control.

Recommended fix High confidence

18.11.3 or later (minimum fixed version: 18.11.3)

  1. Identify your current GitLab version by running `gitlab-rake gitlab:env:info`
  2. Backup your GitLab instance using `gitlab-backup-create` or the Omnibus backup tool
  3. For GitLab Omnibus installations, update by running `sudo apt-get update && sudo apt-get install gitlab-ee` (or gitlab-ce for Community Edition)
  4. For source installations, follow the GitLab upgrade path documentation for your specific version
  5. After upgrade, verify the service is running with `sudo gitlab-ctl status`
  6. Run `sudo gitlab-rake gitlab:check` to verify integrity
  7. Restart GitLab services with `sudo gitlab-ctl restart`
Caveat Upgrading across major GitLab versions may require database migrations and configuration updates; review the upgrade path documentation before proceeding

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

Fix this in GitLab Scoped from the published advisory
  • Consultation2.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
16.0 hours of engineering $2,800
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,480.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-1659 — 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-2026-1659 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