It turns out that one of the Firefox add-ons that was thought to have Trojans were clean and innocuous.
Mozilla said last week that the Win32.LdPinch.gen Trojan was found in v4.0 of the Sothink Web Video Downloader add-on, and the Win32.Bifrose.32.Bifrose Trojan was discovered in all versions of Master Filer. Mozilla said that both Trojans will infect the host computer once the user installs the add-ons and re-launches the browser.
Now, Mozilla says that everything is fine with the Sothink Video Downloader; it was all a false alarm.
"Last week, we disclosed two instances of suspected malware in experimental add-ons on AMO. Since that disclosure, we’ve worked with security experts and add-on developers to determine that the suspected trojan in Version 4.0 of Sothink Video Downloader was a false positive and the extension does not include malware," read a Mozilla blog post.
The Master Filer extension, however, is still bad: "The same investigation also confirmed that the Master Filer extension included a valid instance of a trojan. Our estimate of 6,000 affected downloads has been revised to under 700. The Sothink Video Downloader has been re-enabled on AMO. We apologize to our users and the developers of Sothink for any inconvenience this has caused."
