PandaLabs reports: the largest number of infections in April was aroused by Trojans and advertising software

Once Sdbot.ftp worm has been at the top of rating for more than a year, now is no longer the most frequently detected malicious code. Advertising software that occasioned 27% of the total infections turned to be the most active category of malicious software in April. Trojans which are amounted in 25% are the second category that caused the great number of incidents. Advertising software traces internet-activity of users (visited pages, the search words ...), and uses this information to demonstrate the extremely personalized advertising. â€œAdvertising software has a very easy way of spreading â€“ it is usually hidden inside the legal utilities. Mostly users just donâ€™t understand the risk, and donâ€™t hurry to remove these programs. Thatâ€™s why this type of malicious software has received such widespread and readily used by cyber-criminalsâ€, explains Luis Corrons, technical director of PandaLabs. Trojans are the second of the two most dangerous threats that exist today. The number of infections caused by this type of malicious software is constantly growing in the last several months. Indeed, according to the results of the first quarter of 2007, Trojans have become the most active category of malicious code. â€œThere are two reasons for this. First, Trojans are the most appropriate tool for stealing of confidential information (bank data, e-mail accounts to send spam, etc.), which easily can be turned into profit. Besides, Trojans are more insidious than other technologies of data stealing, for example, phishingâ€, adds Korrons. The remaining incidents were caused by different types of malicious code: worms (8%), backdoor-Trojans (5%), spies (3%), bots (3%) and others. The biggest news of this month is the fact that Sdbot.ftp is no longer the most frequently detected copy of malicious software. Being on the top of the list for more than a year, Sdbot.ftp has fallen immediately to the fifth place this month. In the list of threats, the most often detected by free online antivirus Panda ActiveScan, appeared 6 novelties, and three of them have also become the most dangerous copies of April. The first is Instadia. This is a cookie which is installed on computers from some web pages. As it is usually the case with such codes, it canâ€™t harm itself, but can be used in harmful purposes by other code. The second place among the most active threats of last month took KillAV.FW. This is Trojan designed for stealing confidential information from computers. Downloader.NOE, which has the same functions, took the third place in the list. On the fourth place is Brontok.H, the worm which for several months already is not leaving the top of the ratings. Sdbot.ftp, as it was already mentioned, is on the fifth place. On the sixth place is Puce.E â€“ another long-liver of the rating. This worm is distributed through peering networks. Trojan Clicker.ZL is on the seventh place. On the eighth and ninth place Agent.DIL and KillAV.FG are situated accordingly: the first is designed to support invasion into infected computers. The second is Trojan which violates the correct operation of some security solutions and connects to a server in order to control the infected computer remotely. This Trojan belongs to the family KillAV.FW. Last in the list is Spylocked. It is the advertising software, which is distributed as security utility, supposedly capable of detecting on computers the Malware. Its aim is to make the user to buy this protection product. If the user does so, the product, of course, donâ€™t detect any malicious code. This malicious software has already been distributed earlier under names SpywareQuake or VirusBurst.