In the two years since the Win32/Olmarik family of malware programs (also known as TDSS, TDL and Alureon) started to evolve, its authors have implemented a notably sophisticated mechanism for bypassing various protective measures and security mechanisms embedded into the operating system. Read more here Reverse Engineering Malware
The fourth version of the TDL rootkit family (TDL4) is the first reliable and widely spread bootkit to target x64 operating systems (Windows Vista and Windows 7). Since TDL4 started to spread actively in August 2010, several versions of the malware have been released. By comparison with its predecessors, TDL4 is not just characterized by modification of existing code, but to all intents and purposes can be regarded as new malware. Among the many changes that have been applied as it developed, the most radical were those made to its mechanisms for self-embedding into the system and surviving reboot. One of the most striking features of TDL4 is its ability to load its kernel-mode driver on systems with an enforced kernel-mode code signing policy (64-bit versions of Microsoft Windows Vista and Windows 7) and perform kernel-mode hooks with kernel-mode patch protection policy enabled. This makes TDL4 a powerful weapon in the hands of cybercriminals. In this article, we consider the PPI (Pay Per Install) distribution model used by both TDL3 and TDL4, and the initial installation.
We recently undertook a project to update the hands-on labs in our Reverse Engineering Malware course, and one of our InfoSec Resources Authors, Giuseppe "Evilcry" Bonfa, defeated all of the anti-debugging and anti-forensics features of ZeroAccess and traced the source of this crimeware rootkit:
InfoSec Institute would classify ZeroAccess as a sophisticated, advanced rootkit. It has 4 main components that we will reverse in great detail in this series of articles. ZeroAccess is a compartmentalized crimeware rootkit that serves as a platform for installing various malicious programs onto victim computers. It also supports features to make itself and the installed malicious programs impossible for power-users to remove and very difficult security experts to forensically analyze.