Deserialization of Untrusted Data in GitLab

Answer in brief

CVE-2026-87719 records a Unknown severity vulnerability in Deserialization of Untrusted Data in GitLab. The current sources do not mark it as known exploited. The current feed maps GitLab/GitLab (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 12, 2026Updated Sep 12, 2026Source checked Sep 12, 2026First seen by HOL Sep 12, 2026Material review Sep 12, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps GitLab/GitLab (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
GitLab/GitLabgeneric	>=18.3 <19.1.8 \|\| >=19.2 <19.2.6 \|\| >=19.3 <19.3.2	19.1.8, 19.2.6, 19.3.2

Recommended response

Check inventory. Check lockfiles and deployed manifests for GitLab/GitLab.
Review the reported fix. Update GitLab/GitLab to 19.1.8 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 12, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 12, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 12, 2026

Sources and claim methodology

Upstream source description

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.

Quoted source text, attributed separately from HOL analysis.