CVE-2026-100571: OpenClaw before 2026.8.1 SMS Webhook Rate Limit Bypass

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-26 · updated 2026-09-28
Weakness: CWE-400

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.

Affected products

OpenClaw: from 2026.6.6 before 2026.8.1 — fixed in 2026.8.1

How to fix

Upgrade to a fixed version: OpenClaw 2026.8.1. Check the vendor advisory for mitigations.

References

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