(what our keyword does):
Show you how to extract (like IAM credentials) Explain the differences between IMDSv1 and IMDSv2 Provide a Python script to automate this process
Utilize AWS CloudWatch and AWS GuardDuty to track anomalous access patterns to your instance metadata endpoints. Share public link
The specific notation provided in the prompt— curl-url-http-3A-2F-2F... —highlights how these endpoints are often represented in logs, documentation, or attack payloads.
: 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 curl-url-http-3A-2F-2F169.254.169.254-2Flatest-2Fapi-2Ftoken
This string represents a critical command used to secure Amazon Web Services (AWS) infrastructure. It fetches a session token for the Instance Metadata Service Version 2 (IMDSv2). Decoding the Keyword
In v1, a vulnerable web application could be tricked into visiting http://169.254.169.254/latest/meta-data/iam/security-credentials/ . The metadata service would return sensitive credentials in the HTTP response body, which the attacker could then capture.
Modern firewalls and applications often strip out or block unrecognized custom headers. By requiring specific headers for both token creation and token usage, AWS leverages existing network defenses to block unauthorized access attempts. Migration and Enforcement Best Practices
To understand why the /latest/api/token endpoint is so important, it helps to look at how metadata retrieval has evolved. IMDSv1 (The Legacy Method) (what our keyword does): Show you how to
: IMDSv2 strictly enforces the use of the PUT method to generate a token. This blocks basic SSRF attacks, as most SSRF vulnerabilities only allow GET requests.
I notice you've shared what appears to be a URL encoded string that decodes to:
: Pass that token in an HTTP header ( X-aws-ec2-metadata-token ) during subsequent GET requests. Breaking Down the Command
curl -H "X-aws-ec2-metadata-token: $TOKEN" http://169.254.169.254/latest/meta-ware/iam/security-credentials/ROLE_NAME : Even if an attacker can execute a
curl http://169.254.169.254/latest/api/token
By requiring a session token, AWS adds a layer of defense against: : Preventing accidental exposure.
: IMDSv2 requires a PUT request to ensure that simple GET-based SSRF vulnerabilities cannot trigger a token generation.
: Once you have the $TOKEN , you use it in subsequent requests to fetch metadata (like IAM credentials) by adding the header -H "X-aws-ec2-metadata-token: $TOKEN" . Wiz x Cloud Security Championship: Perimeter Leak