Legitimate penetration testers and internal security teams routinely use automated scanners to test web applications for input validation flaws. Scanners will input variations of the IMDSv2 token URL into query parameters, form fields, and HTTP headers to see if the application attempts to connect out to the metadata address. Malicious Reconnaissance
(advanced) Allow only the root user or specific GIDs to connect to 169.254.169.254:80 using owner module.
The keyword refers to the curl command used to retrieve a session token from the Amazon Web Services (AWS) Instance Metadata Service Version 2 (IMDSv2) .
In 2019, Capital One suffered a massive data breach where an attacker exploited a SSRF vulnerability to access a server's metadata. In the older IMDSv1, a single GET request could yield sensitive IAM role credentials. AWS responded by introducing , which requires a "session-oriented" approach: Step 1 : Use a PUT request to generate a temporary token. curl-url-http-3A-2F-2F169.254.169.254-2Flatest-2Fapi-2Ftoken
Originally, cloud metadata services were simple and dangerous.
Blocks unauthorized external requests using strict network hops. How the API Token Command Works
In (the latest version), the workflow is: The keyword refers to the curl command used
curl http://169.254.169.254/latest/api/token
: To get the token, you must use a PUT request , which is a key security upgrade from the older version (IMDSv1) that only required simple GET requests. Why Is This Command Important? Medium·Gerald Nguyen
Here's what you might do with curl to get an API token: AWS responded by introducing , which requires a
When you see this command in logs, a payload, or a URL-encoded string like ours, it means someone is .
If you are a developer or security researcher:
TOKEN=$(curl -X PUT "http://169.254.169.254/latest/api/token" -H "Content-Type: text/plain") curl -H "X-aws-ec2-metadata-token: $TOKEN" http://169.254.169.254/latest/meta-data/instance-id