CVE-2026-94094 OpenClaw Canvas Host Route server.ts createCanvasHostHandler denial of service
Remote attackers can cause denial of service in OpenClaw Canvas Host by exploiting unbounded file buffering in the createCanvasHostHandler function.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-94094?
CVE-2026-94094 is a medium-severity denial of service vulnerability in OpenClaw, published on 20 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official 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.
Weakness: CWE-404
Which versions are affected by CVE-2026-94094?
How do I fix CVE-2026-94094?
No fix has been published for CVE-2026-94094 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-94094 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-94094 exists.
Sources
Also known as GHSA-24pq-v99h-hj63.