Troj/JavaDl-NJ

ESG security analysts have received reports of a backdoor Trojan infection that targets multiple systems. It seems that this infection begins with a JavaScript Trojan detected as Troj/JavaDl-NJ. This Trojan can be found on hacked websites. One recent example was the website for a Colombian transport company. When the victim makes contact with the hacked website, Troj/JavaDl-NJ – a JAR JavaScript file – automatically triggers and asks the computer user for permission to run. Victims, who believe the website to be trustworthy, may allow the Troj/JavaDl-NJ Java applet to run. Once this happens, Troj/JavaDl-NJ will detect the victim's operating system and then access a remote server in order to download a backdoor Trojan that matches the victim's operating system. There are three versions of Troj/JavaDl-NJ's associated backdoor Trojan. These target Windows, Linux or Mac OSX operating systems. If you believe that you have been exposed to Troj/JavaDl-NJ, ESG malware researchers strongly recommend running a full scan of your computer with a reliable anti-malware application.

Traditionally, Mac OSX and Linux are considered much more secure from malware than Windows operating systems. However, malware that takes advantage of third-party software, such as Java or Flash, is on the rise. ESG malware researchers cannot recommend using any operating system without the protection of a reliable anti-virus program. Mac OSX and Linux computer users are especially vulnerable since Windows computer users are more accustomed to protecting their computer with anti-malware software than users of other operating systems. Troj/JavaDl-NJ will exploit vulnerabilities in Java as well as using a bit of social engineering to deliver its payload.

Protecting Your Computer from a Troj/JavaDl-NJ Infection

Since Troj/JavaDl-NJ is a JavaScript Trojan, disabling Java on your web browser ensures that you will not become exposed to a Troj/JavaDl-NJ infection. In fact, it is usually a good idea to keep JavaScript disabled unless you absolutely need it. It is also a good idea to use a proved anti-malware scanner that is fully updated. However, the best way to protect yourself from Troj/JavaDl-NJ and other malware is to use common sense when going online. Even though a normally reliable website may be hacked in order to deliver Troj/JavaDl-NJ, it will still ask for your permission to run the malicious Java applet. If you are not absolutely sure what something is, ESG security researchers advise against authorizing its execution or downloading it onto your hard drive.