This piece of news only affect Vietnamese users as the Vietnam language package was infected with malware trojan called e Xorer, and so if you downloaded this language pack in the last few weeks run a scan and the trojan should be picked up. Although this trojan is only a couple of months old and so I don't think everyone has something for it, but check at your vendors website and see if they have a solution for it. As for the cause of this infected plugin, they assume the authors computer was infected at the time when they upload this plugin to the mozilla website.

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How does a trojan get into a file like that before you upload it? That kind of worries me as to how many other things we download can be infected. That also leaves an excuse for people to get out of blame. Great catch though.

Scary enough all a trojan needs is a single HTML file to work its way through. I should have mention that in the part were they had an idea how the plugin got infected. Thats all it takes for a website to get infected is just a single html file and when that user either goes to the website itself or that page his or her computer will get infected.