Executive brief
Tencent BrowserSkill is an AI automation tool that controls web browsers and captures page content. A flaw in its local daemon's WebSocket security allows attackers to register a malicious browser extension that passes authentication checks, enabling them to intercept and alter page data, DOM elements, and screenshots seen by the AI agent.
Technical details
The vulnerability is an authentication bypass in the WebSocket origin validation of BrowserSkill's local daemon, which incorrectly accepts any chrome-extension origin containing 32 characters in the a-p range. An attacker can register a malicious extension that connects to the daemon as a trusted browser client without proper authentication, gaining the ability to intercept, manipulate, and exfiltrate page content and screenshots.
Affected products
- Tencent BrowserSkill through 0.3.0
Timeline
- 2026-09-20: disclosed