Pre-Pwned AMI Images in Amazon's AWS public instance store
Last Updated: 2018-09-21 13:28:05 UTC
by Johannes Ullrich (Version: 1)
I keep getting reports about AMI images in Amazon's AWS, which come "pre-pwned." These images typically include for the most part crypto coin miners, but the also include backdoors or more subtle malicious modifications.
One reason users fall for these images appears to be that they search for images without considering the "owner" of the image. This way, you may fall for look-alike images that claim include a popular Linux distribution or that even offer fully patched versions of this distribution.
What I am looking for right now is current examples of such malicious images. If you are aware of any, please let me know.
Just like whenever you use an external component, it is important to secure your "supply chain." In this case, you need to stick to images created by reputable sources (for example Amazon itself should be considered reputable). But in a couple of cases, I was told that vendors offer images with their software preinstalled, that are based on backdoored images. This is likely due to the vendor not performing their due diligence.
Again: Right now I am looking for examples, so if you have one, please use our contact form (https://isc.sans.edu/contact.html) to let me know how to find it and more importantly, how you came across it.
Johannes B. Ullrich, Ph.D. , Dean of Research, SANS Technology Institute