CVE-2026-35646

OpenClaw before 2026.3.25 contains a pre-authentication rate-limit bypass vulnerability in webhook token validation that allows attackers to brute-force weak webhook secrets. The vulnerability exists because invalid webhook tokens are rejected without throttling repeated authentication attempts, enabling attackers to guess weak tokens through rapid successive requests.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/openclaw/openclaw/commit/0b4d07337467f4d40a0cc1ced83d45ceaec0863c
https://github.com/openclaw/openclaw/security/advisories/GHSA-mf5g-6r6f-ghhm
https://www.vulncheck.com/advisories/openclaw-pre-authentication-rate-limit-bypass-in-webhook-token-validation

Configurations

No configuration.

History

09 Apr 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-09 22:16

Updated : 2026-04-13 15:02

NVD link : CVE-2026-35646

Mitre link : CVE-2026-35646

CVE.ORG link : CVE-2026-35646

JSON object : View

Products Affected

No product.

CWE

CWE-307

Improper Restriction of Excessive Authentication Attempts

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