Prompt injection in AWS AgentCore Harness default config lets the root shell tool steal plaintext AgentCore Identity credentials
Unit 42 researchers found that in default AWS AgentCore Harness deployments, prompt injection can steer the agent's built-in shell tool to exfiltrate plaintext credentials resolved from AgentCore Identity. The shell tool is enabled by default and runs as root, in the same UID as the harness runtime (PID 1, python3.10 -m loopy.server). Tha…