knowns before 0.30.0 Path Traversal via code.replace MCP action (CVE-2026-86541) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-86541

knowns before 0.30.0 Path Traversal via code.replace MCP action

Answer in brief

CVE-2026-86541 records a Unknown severity vulnerability in knowns before 0.30.0 Path Traversal via code.replace MCP action. The current sources do not mark it as known exploited. The current feed maps knowns-dev/knowns (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 7, 2026Updated Sep 7, 2026Source checked Sep 8, 2026First seen by HOL Sep 7, 2026Material review Sep 7, 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 knowns-dev/knowns (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
knowns-dev/knownsgeneric	>=0 <0.30.0	0.30.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for knowns-dev/knowns.
Review the reported fix. Update knowns-dev/knowns to 0.30.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 7, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 7, 2026

Sources and claim methodology

Upstream source description

knowns versions before 0.30.0 contain a path traversal vulnerability in the handleCodeReplace() function that allows attackers to overwrite arbitrary files outside the project root. Attackers can supply absolute paths or relative paths containing directory traversal sequences to write malicious content to sensitive files like shell startup scripts or SSH configuration files.

Quoted source text, attributed separately from HOL analysis.