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Showing posts from February, 2019

Exploiting meta-data on AWS

Introduction:
Metadata server: Every EC2 instance has some user scripts which can be used to pull configuration to launch that EC2 instance. Those configs are stored on a Metadata server (169.254.169.254) 'private' to that Ec2 instance. Each time an Ec2 instance starts , AWS attached the " meta data server" to it, which can be accessed from the instance itself using http://169.254.168.254. The instance meta-data stores information such as :AMIid, Private IP address, Instance Type etc...and...

User-data: OS boot scripts:
AWS allows you to boot up the EC2 using a custom User-data scripts- such as web application, Apache web server, keys. credentials etc. This script, also called user data, is stored by AWS in the instance metadata and retrieved by the OS during boot.

Instance profile:
When EC2 instance wants to access other services such as S3, it uses credentials to access it. Instance profiles give Ec2 instances a way to access AWS services. AWS creates a unique set of…