OpenClaw Webhook Reply Rebinding Vulnerability in Synology Chat

A vulnerability in OpenClaw versions prior to 2026.3.22 allows for the rebinding of webhook replies in Synology Chat. This issue arises from the use of mutable usernames for matching instead of stable numeric user identifiers. Attackers can exploit this by changing usernames to redirect replies to unintended users, bypassing the original recipient binding established in webhook events.

Impact

Exploitation of this vulnerability allows for the unauthorized reallocation of chat replies to different users, potentially leading to miscommunication or information leakage.

Reproduction

To reproduce this vulnerability, first configure a Synology Chat account in OpenClaw with the 'dangerouslyAllowNameMatching' option enabled. This will allow the use of mutable usernames for reply delivery. Next, send a message that triggers a webhook reply. After the reply is sent, change the username of the intended recipient to one that is not associated with the original webhook event. The reply will be redirected to the new username, demonstrating the vulnerability.

Remediation

Users can update to OpenClaw version 2026.3.22 or later, where this vulnerability has been fixed. Instructions for updating can be found in the OpenClaw documentation.