Vulnerability · Published Apr 9, 2026 · Assigned by VulnCheck

CVE-2026-35646OpenClaw < 2026.3.25 - Pre-Authentication Rate-Limit Bypass in Webhook Token Validation

Medium 4.8

In plain English

A medium-severity security flaw in OpenClaw from OpenClaw. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 16% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.8Medium

Exploit odds (30 days)0.2%top 83.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	openclaw	2026.3.28	GHSA-mf5g-6r6f-ghhm

Affected products (as reported)

Vendor	Product	Versions
OpenClaw	OpenClaw	0 – before 2026.3.25

Weakness: CWE-307 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

References

GitHub Security Advisory (GHSA-mf5g-6r6f-ghhm) vendor-advisory
Patch Commit patch
VulnCheck Advisory: OpenClaw < 2026.3.25 - Pre-Authentication Rate-Limit Bypass in Webhook Token Validation third-party-advisory