The company Doctor Web, provides information about a new update backdoor, which is one component of a large and actively growing bot-network Tdss. In the components of malicious programs used to make the bot-network Tdss work, apply a lot of modern methods of protection from discovery, as well as techniques that hamper the analysis of malicious files. Among them, in particular, are polymorphic packers, rootkit techniques to hide in the system. Thus, in the arsenal of new backdoors, experts found the company of Doctor Web, there is a feature that lets you disable file antivirus monitors. There are also techniques to hide from detection by some popular antirutkitami. New update BackDoor. Tdss can download other malicious modules with pre-trained servers. After that, backdoor or runs them for execution, or introduces into the memory system processes. Distributed BackDoor. Tdss several quite popular in recent ways - using the operation of a number of vulnerabilities in Windows, and a supposedly codec for viewing video files. The company Doctor Web, in conjunction with a wide spread of malicious programs that use known vulnerabilities to infiltrate the family of operating systems Windows, recommends that all users in time to install updates to the systems used. Also recommended to use anti-virus with automatic updates of virus databases is not only, but also other components of anti-virus to more effectively counter the contemporary Internet threats, using new techniques to hide in the system.