Over half a million Apple's Mac computers hit by Trojan

Over 550,000 Apple Mac computers have been reportedly affected by a Trojan attack, a Russia based antivirus maker Doctor Web reported. According to the firm, this attack is affecting computers running on Mac OS X software.

As per a blog post by the company, Most of the infected machines are located in United States and Canada. Although Apple has already patched the vulnerability, there may be thousands of computers out there, who may not have applied the security patch.

Dubbed as a BackDoor.Flashback.39 Trojan, it is infecting the computers after a user visits a website containing the Trojan and the infection happens silently in the background. The security vulnerability that is allowing the Trojan to infect user's computer exists in Java, a popular programming language for making webpages. Security researchers at Docter Web have already identified a large number sites housing the exploit.

"This once again refutes claims by some experts that there are no cyber-threats to Mac OS X," stated Docter Web in the blog post.

It is important to note here that the reported security vulnerability lies in Java, which isn't an Apple product. Cupertino has even stopped bundling it as a default add-on beginning 2011 with Lion release. It is not even required for viewing most of the websites, so if you want, you can just go ahead and turn off Java in your web browsers by going to Java Preferences utility.

If you do require Java, it is recommended that you download and install a security update released by Apple from support.apple.com/kb/HT5228 to prevent infection of your systems by BackDoor.Flashback.39.