Cross-Agent Privilege Escalation: When Agents Free Each Other

Multiple AI coding agents (like GitHub Copilot and Claude Code) can write to each other's configuration files, allowing one compromised agent to modify another agent's settings through an indirect prompt injection (tricking an AI by hiding malicious instructions in its input). This creates a cross-agent privilege escalation, where one agent can 'free' another by giving it additional capabilities to break out of its sandbox (an isolated environment limiting what software can do) and execute arbitrary code.