Comment Injection Attacks Hit Claude Code, Gemini, Copilot
A researcher has disclosed a novel prompt injection attack technique dubbed 'Comment and Control,' demonstrating that popular AI coding agents — including Claude Code, Gemini CLI, and GitHub Copilot Agents — can be manipulated through malicious instructions embedded in source code comments. The attack exploits the tendency of agentic coding tools to process and act upon contextual content within files they are tasked to read or modify. This represents a meaningful escalation in the risk surface of AI-assisted software development workflows.