AWS Trusted Remote Execution (REX) - Command Injection in Setup Docs

AWS Systems Manager's Trusted Remote Execution setup documentation contained an OS command injection vulnerability (CVE-2026-122193) in example scripts. Users with SSM document invocation permissions could inject malicious commands to execute outside the REX sandbox. Good news: this bug only affects the documentation examples, not shipped REX versions. Check AWS's advisory for patched guidance—no immediate action needed unless you're using the old example scripts.