Forever Security discloses AGENTS.md attack that hijacks Codex and Claude Code
Overview
Forever Security discloses an attack in which a malicious AGENTS.md file, placed in a user's Downloads folder by a web page, makes AI coding agents run attacker-supplied instructions.
In the security firm's reproduction, the attack succeeded over 90% of the time against Codex and about 50% against Claude Code, according to QbitAI's report on the disclosure. The firm published a YouTube video of the attack. QbitAI reports that the article also lists checks users can run to detect it.
Written by AI from the articles below · updated Nov 7, 12:10 AM ET
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- QbitAINewsPickForever Security discloses AGENTS.md attack that hijacks Codex and Claude Code
AIForever Security says a malicious AGENTS.md file, dropped into the Downloads folder by a web page, can make AI coding agents such as Codex and Claude Code run attacker instructions. In its reproduction, the attack succeeded over 90% of the time against Codex and about 50% against Claude Code. The article lists checks users can run and argues that agent-era security must change.
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