Auth bypass in Google Cloud Dialogflow Cx Messenger

CVE-2025-13427

An authentication bypass vulnerability in Google Cloud Dialogflow CX Messenger allowed unauthenticated users to interact with restricted chat agents, gaining access to the agents' knowledge and the ability to trigger their intents, by manipulating initialization parameters or crafting specific API requests. All versions after August 20th, 2025 have been updated to protect from this vulnerability. No user action is required for this.

Vulnerability class: Broken Authentication

EPSS: 0.004 (35.1th percentile) — read the EPSS interpretation.