The Trojan-Downloader.JS.Agent.gsv Infection
The kind of pseudo-random domain generation that the Trojan-Downloader.JS.Agent.gsv uses has been observed in botnets and backdoor Trojans generating domains for command and control servers. This approach is quite new in the case of browser redirect Java scripts. The Trojan-Downloader.JS.Agent.gsv itself is a Trojan downloader that uses a malicious iFrame that is attached to an HTML file. It generates a random domain name with sixteen characters, with a .RU ending (indicating that the domain is located in the Russian Federation).
Why the Trojan-Downloader.JS.Agent.gsv Generates New Domains
The technique of randomly generating new domain names allows criminals to avoid blacklisting. Every day, the Trojan-Downloader.JS.Agent.gsv generates a new domain name. This means that adding malicious URLs to a blacklist can be pointless due to the fact that new ones are generated constantly. Fortunately, these domain names are not entirely random and use an algorithm that takes its seed from the current date. With this information, PC security researchers can predict future domain names, allowing them to blacklist them preemptively. If you administrate a website, it is important to update your website's software and to apply all available security patches. ESG security analysts also advise changing all sensitive passwords, especially for FTP, SFTP and SSH accounts.
This article is provided "as is" and to be used for educational information purposes only. By following any instructions on this article, you agree to be bound by the disclaimer. We make no guarantees that this article will help you completely remove the malware threats on your computer. Spyware changes regularly; therefore, it is difficult to fully clean an infected machine through manual means.