Unsafe Deserialization in Gitlab (CVE-2026-87719)
Summary
Vulnerability in Gitlab (CVE-2026-87719). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
GitLab has remediated an issue in GitLab EE affecting all versions from 18.3 before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2 that under certain conditions could allow an authenticated user with Duo Chat access to obtain Advanced Search instance configurations and sensitive credentials using a specially crafted GraphQL subscription argument to bypass serialization and perform server object lookup.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-87719 has been found in Gitlab.
Successful exploitation can lead to full system takeover. CVSS score: 9.9/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Gitlab CVE-2026-87719" on the vendor's site.
CVE-2026-87719 (Gitlab) — CWE-502 / CVSS v3 9.9
Attack vector: remote (network-reachable) / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Unsafe deserialization (CWE-502) exists in Gitlab.
Check the vendor advisory for the affected versions of Gitlab.
Severity: Critical (CVSS 9.9/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Gitlab' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Gitlab' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Gitlabを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- web gitlab.com
- web hackerone.com
- web nvd.nist.gov
- web github.com