Follow the principle of least privilege.
If an attacker can trick your application into "calling back" to this URL, your server will fetch its own secret AccessKeyId SecretAccessKey SessionToken and send them back to the attacker. Recommended Security Post
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Disclaimer: The information in this article is for educational purposes only. Unauthorized access to computer systems is illegal.
169.254.169.254 is the crown jewels of AWS internal networking. Its appearance in plaintext outside an EC2 instance is a five-alarm fire. Follow the principle of least privilege
Now, let's dissect the callback URL: http://169.254.169.254/latest/meta-data/iam/security-credentials/ .
Notes and risks:
callback-url-http-3A-2F-2F169.254.169.254-2Flatest-2Fmeta data-2Fiam-2Fsecurity credentials-2F
The IP address 169.254.169.254 is a special address reserved for use in cloud computing environments, particularly in Amazon Web Services (AWS). It's known as the "metadata service" or "instance metadata service." This IP address is not routable on the public internet and can only be accessed from within a cloud instance. Share public link Disclaimer: The information in this
The client then includes that token in a custom HTTP header for all subsequent GET requests.
: The EC2 instance can access the metadata service by making HTTP requests to 169.254.169.254 . This IP address is a special link-local address that is always available to EC2 instances. Its appearance in plaintext outside an EC2 instance