In this presentation we will show a new approach to perform on-the-fly malware analysis (even of previously unknown malware), without the need of deploying any instrumentation at the end host before hand.
Our approach leverages the fact that malware quite often comes as a small (in size) "spore", which is then responsible for making the malware persistent on the targeted host and download additional components ("eggs"). Eggs usually come in the shape of executables or DLLs, and extend the capabilities of the spore (password grabbing, URL redirection, etc.)
Our system, we call it Avatar, detect failed attempts to download eggs, and ships back to the suspected malware what we call a "red pill". When the malware executes the red pill, this performs some preliminary checks and can send to an instrumented host a copy of the parent process' executable. In this instrumented (i.e., sand-boxed) environment it is possible to perform real-time analysis of the suspicious program. The red pill can be then remotely instrumented to terminate the monitored process, in case it appears to be a real threat. By doing so, it is possible to effectively contain a large infection.