OpenClaw Canvas Host Route server.ts createCanvasHostHandler denial of service (CVE-2026-94094) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-94094

OpenClaw Canvas Host Route server.ts createCanvasHostHandler denial of service

Answer in brief

CVE-2026-94094 records a Unknown severity vulnerability in OpenClaw Canvas Host Route server.ts createCanvasHostHandler denial of service. The current sources do not mark it as known exploited. The current feed maps n/a/OpenClaw (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 20, 2026Updated Sep 20, 2026Source checked Sep 21, 2026First seen by HOL Sep 20, 2026Material review Sep 20, 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: Not reported

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 n/a/OpenClaw (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
n/a/OpenClawgeneric	2026.9.0 \|\| 2026.9.1 \|\| 2026.9.2 \|\| 2026.9.3 \|\| 2026.9.4 \|\| 2026.9.5	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for n/a/OpenClaw.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 20, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 20, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 20, 2026

Sources and claim methodology

Upstream source description

A flaw has been found in OpenClaw up to 2026.9.5. Affected is the function createCanvasHostHandler of the file extensions/canvas/src/host/server.ts of the component Canvas Host Route. Executing a manipulation can lead to denial of service. The attack can be launched remotely. The exploit has been published and may be used. Fix suggestion's "streaming/size-limit" was never shipped - latest 2026.9.5 still buffers the whole file via readFile() (src/canvas/serve.runtime.ts:17,114), unlike the sibling WS path which caps at 64KB. The vendor was contacted early about this disclosure.

Quoted source text, attributed separately from HOL analysis.