Callback-url-http-3a-2f-2f169.254.169.254-2flatest-2fmeta Data-2fiam-2fsecurity Credentials-2f Jun 2026

Ensure that the IAM roles attached to your instances have the absolute minimum permissions required to function.

The specific path /latest/meta-data/iam/security-credentials/[role-name] hosts temporary security credentials (Access Key ID, Secret Access Key, and Token) associated with the IAM role assigned to that EC2 instance.

Never trust a user‑supplied URL. Implement a strict allowlist of allowed domains or protocols. If you must fetch arbitrary URLs, use a dedicated “fetch proxy” that:

Applications running on an EC2 instance can fetch these credentials by making a GET request to the metadata service. For example, in a Linux environment, you can use curl : Ensure that the IAM roles attached to your

Because most basic SSRF vulnerabilities only allow attackers to make simple GET requests without custom headers, IMDSv2 completely blocks them from accessing the credentials. 2. Input Validation and Whitelisting

Ensure IAM roles attached to EC2 instances only have the permissions necessary to function. Even if credentials are stolen, the damage is minimized. 4. Input Validation and Whitelisting

The article should be well-structured, professional, and educational. It should include explanations, examples, and recommendations. Length: "long article" suggests 1500-2000+ words. Implement a strict allowlist of allowed domains or protocols

: First, an EC2 instance is launched with an IAM role attached. This IAM role defines the permissions the instance has to access AWS resources.

: Because the request originates from within the cloud instance, the cloud metadata service trusts it implicitly under older protocols. It responds with the names of active IAM profiles.

This is clearly targeting the – a well-known internal IP address ( 169.254.169.254 ) used by EC2 instances to expose instance metadata, including IAM role credentials. including IAM role credentials.

[Attacker] --(Sends Payload)--> [Vulnerable Web App] --(Internal Query)--> [IMDS (169.254.169.254)] ^ | |_________________________(Exfiltrates AWS Keys)___________________________________|

CB-20240424-001 Severity: Critical Vector: Server-Side Request Forgery (SSRF) / Configuration Leak