CVE-2026-100571 OpenClaw before 2026.8.1 SMS Webhook Rate Limit Bypass
An attacker can exhaust rate limits to cause temporary SMS loss in OpenClaw deployments behind shared proxies.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-100571?
CVE-2026-100571 is a medium-severity denial of service vulnerability in OpenClaw, published on 26 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
OpenClaw (npm package 'openclaw') versions >= 2026.6.6 and < 2026.8.1 apply the SMS webhook invalid-request rate limit before Twilio signature verification and identify clients only by the raw proxy socket address. In deployments where the SMS/Twilio webhook sits behind a trusted reverse proxy or tunnel so that multiple external clients share one socket address, an unauthenticated remote sender can exhaust the shared pre-authentication rate-limit budget with invalid requests, causing subsequent correctly signed Twilio callbacks to receive HTTP 429 responses. The result is temporary inbound SMS loss while the shared window remains exhausted; the attacker cannot forge a callback or access message data. Fixed in 2026.8.1.
Weakness: CWE-400
Which versions are affected by CVE-2026-100571?
How do I fix CVE-2026-100571?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-100571 being exploited?
There is no known exploitation of CVE-2026-100571 in the wild and no public exploit code.
Sources
Also known as GHSA-r2rq-3p63-8cqm, GHSA-xw48-j584-r73h, MINI-j24c-f2gx-x6wg.