Kaspersky Lab has published rating Malware for March 2009. As a result of Kaspersky Security Network (KSN) in the last month have been formed two viral twenty. The first table of the rating is based on data collected during the 2009 anti-virus product version. This table hold those malicious, advertising and potentially dangerous programs, which were detected on users` computers. In March, the first table of major changes have occurred. In the first place has a network worm Net-Worm. Win32. Kido. ih, also known as Conficker and Downadup. Yet another version of this sensational zlovreda we are unlikely to see in twenty in the coming months:it found the products Kaspersky Labs as a Trojan-Downloader. Win32. Kido. a and no longer has the functionality of network distribution. All malicious, advertising and potentially dangerous program, presented in the first rank, can be grouped under the main categories of threats detektiruemyh us. Their ratio is almost not changed for over three months. And the proportion of self-programming is great. in March to the client was registered 45, 857 unique malicious, advertising and potentially dangerous programs. This figure is virtually no different from the figure for the previous month. The second table provides data on the rating of what the malware most frequently detected in the infected users` computers infected objects. Basically here are the various malicious programs that can infect files. Net-Worm. Win32. Kido. ih distinguished, and the second twenty. Zlovred using a vulnerability in the software, was able to fight for places in the ranking equally with auto programs more popular types. Apparently, this suggests that not all users had to install OS security update last month.