Deserialization in GitLab
CVE-2026-87719
GitLab has remediated an issue in GitLab EE affecting all versions from 18.3 before 18.11.12, 19.0 before 19.0.9, 19.1 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.
Vulnerability class: Insecure Deserialization
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.006 (47.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
Weakness classification (CWE)
References
- gitlab.com/gitlab-org/gitlab/-/work_items/628160 (Broken Link)
- hackerone.com/reports/4012289 (Permissions Required, technical-description, permissions-required, exploit)
Frequently asked questions
- What is CVE-2026-87719?
- CVE-2026-87719 is a critical-severity vulnerability in GitLab, classified under Deserialization of Untrusted Data. CVSS score: 9.9/10. Published 2026-09-12.
- How severe is CVE-2026-87719?
- Critical severity. CVSS v3 base score is 9.9 out of 10.