Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab (CVE-2026-84739) | HOL Guard CVE

High · CVSS 8.7CVE-2026-84739

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in GitLab

Answer in brief

CVE-2026-84739 records a High severity (CVSS 8.7) vulnerability in Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') 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 29, 2026Updated Sep 29, 2026Source checked Sep 29, 2026First seen by HOL Sep 29, 2026Material review Sep 29, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 8.7
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 8.7. 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	>=13.11 <19.2.7 \|\| >=19.3 <19.3.3 \|\| >=19.4 <19.4.1	19.2.7, 19.3.3, 19.4.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for GitLab/GitLab.
Review the reported fix. Source-reported solution: Upgrade to versions 19.2.7, 19.3.3, 19.4.1 or above.

Evidence timeline and material changes

Published upstream
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 29, 2026

Sources and claim methodology

Upstream source description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 13.11 before 19.2.7, 19.3 before 19.3.3, and 19.4 before 19.4.1 that under certain conditions could have allowed an authenticated user to execute arbitrary JavaScript in the context of another user's browser session due to improper sanitization of path components in the merge request diff viewer.

Quoted source text, attributed separately from HOL analysis.