One Extension Could Hijack AI Assistants Across Chrome, Comet, Edge, Opera Neon and Claude
Researchers showed a single browser extension could hijack AI agents in Chrome, Edge, Comet, Opera Neon and Claude in Chrome, earning $20,000 in bounties.
Forever Security demonstrated that a browser extension with two common permissions could seize the trusted page controlling built-in AI assistants in five Chromium-based products and drive the agent, read local files, or access the camera. Chrome's flaw was fixed as CVE-2026-0628 (CVSS 8.8) in Chrome 143.0.7499.192, and Microsoft fixed CVE-2026-55945 (CVSS 4.2) in Edge 150.0.4078.48. Perplexity Comet was the worst case: a hijacked agent could read any file, leak browsing history, take screenshots, and act as the user via an unsecured test subdomain. All attacks require a malicious extension already installed; no in-the-wild exploitation or KEV listing was reported as of September 16, 2026.