OpenClaw versions earlier than 2026.2.12 contain a flaw in the optional BlueBubbles webhook handler that authenticates requests solely on the loopback remoteAddress. Because the handler does not validate proxy‑provided forwarding headers, an attacker can send a request that appears to originate from 127.0.0.1, bypassing the configured webhook password. The result is unauthorized injection of BlueBubbles message and reaction events, allowing the attacker to post arbitrary content through the webhook endpoint.

OpenClaw is the vendor and product; all releases before 2026.2.12 are affected. Any deployment that uses the BlueBubbles plugin and runs behind a reverse proxy is exposed.

The CVSS score of 8.2 indicates high severity, while the EPSS score of less than 1% suggests a low probability of widespread exploitation at present. The vulnerability is not listed in the CISA KEV catalog. The attack vector is network‑remote; an external attacker who can reach the reverse‑proxy front‑end can craft a request that the backend treats as loopback, thereby bypassing authentication. Once authenticated, the attacker can inject arbitrary message events, compromising data integrity and potentially enabling social‑engineering or spam attacks.