Curl-url-http-3a-2f-2f169.254.169.254-2flatest-2fapi-2ftoken New! May 2026
Once you have the $TOKEN , you can access the metadata safely:
The command curl -X PUT "http://169.254.169" -H "X-aws-ec2-metadata-token-ttl-seconds: 21600" is a critical component of modern cloud security within Amazon Web Services (AWS). It represents the transition from the legacy Instance Metadata Service Version 1 (IMDSv1) to the more secure . What is 169.254.169.254? curl-url-http-3A-2F-2F169.254.169.254-2Flatest-2Fapi-2Ftoken
solves this by requiring a session-oriented authentication process: Once you have the $TOKEN , you can
TOKEN=$(curl -X PUT "http://169.254.169" \ -H "X-aws-ec2-metadata-token-ttl-seconds: 21600") Use code with caution. Every EC2 instance can query this address to
curl -H "X-aws-ec2-metadata-token: $TOKEN" http://169.254.169 Use code with caution. Why This Matters for Security
The IP address is a link-local address used by AWS to provide the Instance Metadata Service (IMDS) . Every EC2 instance can query this address to retrieve information about itself—such as its instance ID, public IP, IAM role credentials, and security groups—without needing to call the AWS API externally. The Evolution: From IMDSv1 to IMDSv2
: You must first perform a PUT request to /latest/api/token to generate a temporary session token.