Openclaw cli: OpenClaw's voice-call Twilio replay dedupe now bound to authenticated webhook identity

The voice-call Twilio webhook path in OpenClaw CLI accepted replay/dedupe identity from an unsigned request header (`i-twilio-idempotency-token`). This enabled attackers with one valid signed request to replay that request by changing only the unsigned idempotency header, bypassing replay detection and deduplication. The fix removes trust in the unsigned header and binds replay deduplication to authenticated request material, ensuring dedupe uses verification-derived identity. The vulnerability affects versions >=2026.1.29 and <2026.2.26, with the fix committed in commit 1aadf26f9acc399affabd859937a09468a9c5cb4 and planned for release in version 2026.2.26.

Deployments using the affected voice-call Twilio webhook path could accept replayed webhook events as new events if an attacker had a valid signed request and manipulated the unsigned idempotency header. This could lead to processing duplicate webhook events, potentially causing unintended side effects or resource consumption. The CVSS score is 3.7 (low severity) with no confidentiality, integrity, or major availability impact.

A patch is available and planned for release in OpenClaw CLI version 2026.2.26. Users should upgrade to this version once published to mitigate the vulnerability. The fix removes reliance on unsigned headers for replay detection and binds deduplication to authenticated request identity. No additional mitigation steps are indicated by the vendor advisory.