Curl-url-http-3a-2f-2f169.254.169.254-2flatest-2fapi-2ftoken [updated] Link

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 include that token in the header of all subsequent metadata requests. Breaking Down the Command curl-url-http-3A-2F-2F169.254.169.254-2Flatest-2Fapi-2Ftoken

: Standard WAFs are better at blocking complex PUT requests than simple GET requests. The IP address is a link-local address used

In the past (IMDSv1), metadata was accessible via a simple GET request. While convenient, this was vulnerable to attacks. If an attacker could trick a web application into making a request to that internal IP, they could steal sensitive IAM credentials. Breaking Down the Command : Standard WAFs are

: Even if an attacker can execute a GET request through your app, they cannot easily perform the PUT handshake required to get a token. Conclusion

TOKEN=$(curl -X PUT "http://169.254.169" \ -H "X-aws-ec2-metadata-token-ttl-seconds: 21600") Use code with caution.

: You must first perform a PUT request to /latest/api/token to generate a temporary session token.