: When an AWS instance is launched, it can be configured to use IAM roles. These roles define what AWS resources the instance can access.

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Once the attacker has the credentials, they can configure the AWS CLI and run commands like:

Curious, Alex decided to explore this location. They realized that 169.254.169.254 was a special IP address, known as the link-local address, which was used for communication between systems on the same network.

aws s3 ls --profile stolen aws ec2 describe-instances --region us-east-1

If an EC2 instance has an associated IAM role, a GET request to this specific endpoint will return the for that role in a JSON format. The response typically contains:

Our keyword, request-url-http-3A-2F-2F169.254.169.254-2Flatest-2Fmeta data-2Fiam-2Fsecurity credentials-2F , is essentially a URL that has been URL-encoded and then possibly reformatted for use in logs, configuration files, or attack payloads. Let’s decode it:

To mitigate this risk, you must transition to , which introduces session-oriented requests that cannot be easily exploited by standard SSRF. 1. Enforce IMDSv2

Ensure the IAM roles assigned to your EC2 instances only have the absolute minimum permissions required to perform their tasks. If an instance's credentials are stolen via SSRF, a restricted IAM role prevents the attacker from escalating privileges or accessing sensitive resources like administrative functions or global S3 data stores. 4. Deploy Web Application Firewalls (WAF)

Historically, any process running on the server could query this IP to get information about the instance without providing a password or API key. Decoding the URL Pathway

The URL http://169.254.169 is an AWS Instance Metadata Service endpoint utilized to retrieve temporary security credentials, a common target for Server-Side Request Forgery (SSRF) attacks. Instance Metadata Service Version 2 (IMDSv2) enhances security by implementing session-oriented authentication, mandatory headers, and configurable hop limits to mitigate unauthorized access.