HashJack: Indirect Prompt Injection Targets AI Browsers
⚠️Security researchers at Cato Networks disclosed HashJack, a novel indirect prompt-injection vulnerability that abuses URL fragments (the text after '#') to deliver hidden instructions to AI browsers. Because fragments never leave the client, servers and network defenses cannot see them, allowing attackers to weaponize legitimate websites without altering visible content. Affected agents included Comet, Copilot for Edge and Gemini for Chrome, with some vendors already rolling fixes.
