OpenClaw up to 2026.3.23 Feishu Webhook Endpoint amplification

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in OpenClaw up to 2026.3.23. This impacts an unknown function of the component Feishu Webhook Endpoint. Executing a manipulation can lead to amplification. This vulnerability is registered as CVE-2026-35665. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as problematic was found in OpenClaw up to 2026.3.23. This vulnerability affects an unknown function of the component Feishu Webhook Endpoint. The manipulation with an unknown input leads to a amplification vulnerability. The CWE definition for the vulnerability is CWE-405. The product does not properly control situations in which an adversary can cause the product to consume or produce excessive resources without requiring the adversary to invest equivalent work or otherwise prove authorization, i.e., the adversary's influence is "asymmetric." As an impact it is known to affect availability. CVE summarizes:

OpenClaw before 2026.3.24 contains an incomplete fix for CVE-2026-32011 where the Feishu webhook handler accepts request bodies with permissive limits of 1MB and 30-second timeout before signature verification. An unauthenticated attacker can exhaust server connection resources by sending concurrent slow HTTP POST requests to the Feishu webhook endpoint, blocking legitimate webhook deliveries.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-35665 since 04/04/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 2026.3.24 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Amplification
CWE: CWE-405 / CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: OpenClaw 2026.3.24

Timelineinfo

04/04/2026 CVE reserved
04/10/2026 +6 days Advisory disclosed
04/10/2026 +0 days VulDB entry created
04/10/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-w6m8-cqvj-pg5v
Status: Confirmed

CVE: CVE-2026-35665 (🔒)
GCVE (CVE): GCVE-0-2026-35665
GCVE (VulDB): GCVE-100-356860

Entryinfo

Created: 04/10/2026 20:16
Changes: 04/10/2026 20:16 (76)
Complete: 🔍
Cache ID: 216:D39:103

Once again VulDB remains the best source for vulnerability data.

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