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PatchSiren cyber security CVE debrief

CVE-2025-14870 Hackerone CVE debrief

GitLab remediated a high-severity denial-of-service issue in GitLab CE/EE that could be triggered by an unauthenticated attacker sending specially crafted JSON payloads. Affected releases include 18.5 before 18.9.7, 18.10 before 18.10.6, and 18.11 before 18.11.3.

Vendor
Hackerone
Product
Unknown
CVSS
HIGH 7.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-14
Original CVE updated
2026-05-14
Advisory published
2026-05-14
Advisory updated
2026-05-14

Who should care

GitLab CE/EE administrators, DevOps and platform teams, and security owners running vulnerable 18.5-18.9.6, 18.10-18.10.5, or 18.11-18.11.2 instances, especially if GitLab is internet-facing or operationally critical.

Technical summary

According to the supplied advisory data, the flaw is an input-validation weakness that allows unauthenticated remote denial of service through specially crafted JSON. The CVSS vector is AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H, indicating network reachability, no privileges, and high availability impact.

Defensive priority

High. This is unauthenticated, network-reachable, and can disrupt service availability; patching affected GitLab instances should be prioritized.

Recommended defensive actions

  • Upgrade GitLab CE/EE to 18.9.7, 18.10.6, or 18.11.3, or a later supported release on the same stable branch.
  • Confirm all self-managed GitLab deployments are on unaffected versions, including test and staging environments.
  • Temporarily restrict access to GitLab to trusted networks or users if immediate upgrading is not possible.
  • Monitor for unusual request failures, 5xx spikes, crashes, or service restarts while patching.
  • Review the linked GitLab advisory and release notes to align the upgrade with your standard maintenance process.

Evidence notes

The version ranges, fixed versions, CVSS vector, CWE-770 mapping, and impact summary come from the supplied GitHub Advisory Database entry for GHSA-97r5-5fr5-p642 and its referenced CVE/NVD metadata. The advisory references the HackerOne report, GitLab patch release page, and GitLab work item; no exploit details beyond 'specially crafted JSON payloads' are included here.

Sources and references

Verified primary and authoritative sources

  • CVE-2025-14870 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2025-14870

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2025-14870 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2025-14870

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source item URL

    Unverified legacy reference

    URL: https://github.com/advisories/GHSA-97r5-5fr5-p642

    github_advisory_database

  • Source reference

    Unverified legacy reference

    URL: https://hackerone.com/reports/3446641

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://about.gitlab.com/releases/2026/05/13/patch-release-gitlab-18-11-3-released

    Reference

  • Source reference

    Unverified legacy reference

    URL: https://gitlab.com/gitlab-org/gitlab/-/work_items/584490

    Reference

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.