The specific path /latest/meta-data/iam/security-credentials/ is designed to provide temporary (Access Key ID, Secret Access Key, and Session Token) to authorized applications. Anatomy of the Attack Payload
The provided string is a URL-encoded version of: http://169.254.169.254/latest/meta-data/iam/security-credentials/ Securing the EC2 Instance Metadata Service Secret Access Key
AWS provides the Instance Metadata Service (IMDS) at the non-routable IP address 169.254.169.254 . This service allows applications running on an EC2 instance to retrieve information about the instance itself without needing an external API call. Secret Access Key