Vulnerability · Published Apr 23, 2026 · Assigned by VulnCheck

CVE-2026-41343OpenClaw < 2026.3.31 - Denial of Service via LINE Webhook Handler Pre-Auth Concurrency

Medium 5.3

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 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.5%top 60.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

OpenClaw before 2026.3.31 lacks a shared pre-auth concurrency budget on the public LINE webhook path, allowing attackers to cause transient availability loss. Remote attackers can flood the webhook endpoint with concurrent requests before signature verification to exhaust resources and degrade service availability.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	openclaw	2026.3.31	GHSA-qcc3-jqwp-5vh2

Affected products (as reported)

Vendor	Product	Versions
OpenClaw	OpenClaw	0 – before 2026.3.31

Weakness: CWE-799 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

GitHub Security Advisory (GHSA-qcc3-jqwp-5vh2) vendor-advisory
Patch Commit patch
VulnCheck Advisory: OpenClaw < 2026.3.31 - Denial of Service via LINE Webhook Handler Pre-Auth Concurrency third-party-advisory