OpenClaw up to 2026.9.5 Canvas Host Route server.ts createCanvasHostHandler denial of service

CVSS Meta Temp Score
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CTI Interest Score
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3.9$0-$5k1.12+

Summaryinfo

A vulnerability was found in OpenClaw up to 2026.9.5. It has been rated as problematic. Affected by this vulnerability is the function createCanvasHostHandler of the file extensions/canvas/src/host/server.ts of the component Canvas Host Route. The manipulation leads to denial of service. This vulnerability is listed as CVE-2026-94094. The attack may be initiated remotely. In addition, an exploit is available. 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.

Detailsinfo

A vulnerability was found in OpenClaw up to 2026.9.5. It has been rated as problematic. This issue affects the function createCanvasHostHandler of the file extensions/canvas/src/host/server.ts of the component Canvas Host Route. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-94094. The exploitation is known to be easy. The attack may be initiated remotely. Technical details as well as a public exploit are known. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

The exploit is available at github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure. 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.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 3.9

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/20/2026 Advisory disclosed
09/20/2026 +0 days VulDB entry created
09/20/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-94094 (🔒)
GCVE (CVE): GCVE-0-2026-94094
GCVE (VulDB): GCVE-100-408023
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 09/20/2026 11:12
Changes: 09/20/2026 11:12 (58)
Complete: 🔍
Submitter: pengguogood
Cache ID: 216::103

Submitinfo

Accepted

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