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February 5, 2010 1:31 PM PST

Mozilla yanks infected add-ons, warns users

by Seth Rosenblatt
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Mozilla on Friday pulled two programs from its Firefox browser add-on site for containing malware. Sothink Web Video Downloader 4.0 and all versions of Master Filer were found to contain Trojan horse code aimed at Windows users.

In a blog post, Mozilla stated that the Master Filer add-on was able to bypass AMO's security tests.

Mozilla user CatThief discovered the threat, it said. And when Mozilla added two more security checks to its vetting process and rescanned its entire catalog, it discovered that version 4 of the Sothink Web Video Downloader also contained a Trojan horse program. Sothink Web Video Downloader contained Win32.LdPinch.gen, and Master Filer contained Win32.Bifrose.32.Bifrose.

Master Filer was removed from Mozilla's Firefox add-on site on January 25, and the Sothink video downloader was removed on Tuesday. CNET Download.com ceased hosting the Sothink add-on on Friday before noon.

Sothink Web Video Download 5.5.90819 had been a mildly popular Firefox add-on at Download.com, receiving 697 downloads in the past week and 63,716 downloads since it was first added to the site in June 2007.

Because the Trojan horse programs are tied to Firefox, Mozilla warns, host computers won't be infected until Firefox started. Uninstalling either add-on is only part of the solution, if the infection has already attacked the host computer. Mozilla recommends that users who suspect that they are infected use one of the following security applications to sweep and clean their computers after uninstalling the threatening add-on:

  • Antiy-AVL
  • Avast
  • AVG
  • GData
  • Ikarus
  • K7 AntiVirus
  • McAfee
  • Norman
  • VBA32
  • Infected users should note that only Avast and AVG are free.

    Mozilla did not immediately respond to requests for comment. We'll update this post as we learn more.

    Seth peers into the deep, dark corners of software so that you don't have to. He has yet to suffer a single nightmare about OS/2. You can follow him on Twitter.
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    by buffalo2wheeler February 5, 2010 1:59 PM PST
    "Because the trojans are tied to Firefox, Mozilla warns, host computers won't be infected until Firefox started."

    Installing an add-on to Firefox requires a restart of Firefox, so host computers would be infected immediately. The phrase "won't be infected" doesn't apply.
    Reply to this comment
    by redmarine February 5, 2010 2:50 PM PST
    Not if they didn't restart the browser immediately after installing the add-ons and somehow stumbled upon this article.This would give them time to uninstall the plugin.

    Unlikely but sure.
    by Seaspray0 February 5, 2010 3:43 PM PST
    because we all stumble across internet articles without using the browser? Ya know, that's just crazy enough to work! I'm convinced.
    by lordmorgul February 5, 2010 9:04 PM PST
    It does not require a restart immediately. It requires a restart before the addon will work, sometimes, but not always, and you can put that restart off for as long as you want. What was claimed is accurate, even if it is not very likely to save anyone.
    by Timetogetill7 February 6, 2010 12:33 AM PST
    Seaspray...yeah because on most computers people typically only use one browser?
    [CNET editor's note: Personal attack deleted.]
    by baconstang February 5, 2010 2:05 PM PST
    Why do I bother reading these articles to see if latest malware affects Mac OSX?
    Reply to this comment 3 people like this comment
    by monkeyfun14 February 5, 2010 2:12 PM PST
    Idk I ask you the same thing. But I think your main objective is to be a troll.
    18 people like this comment
    by chrisszy08 February 5, 2010 2:16 PM PST
    Why do you bother making pointless post like this? Who knows? More importantly, who cares? Move along troll.
    6 people like this comment
    by aka_tripleB February 5, 2010 3:13 PM PST
    Why did I bother reading your comment, then comment on your comment?
    4 people like this comment
    by hybreda February 5, 2010 9:56 PM PST
    Ahh, just another useless Mac-boaster that forgets all the hurried patches Apple applied to OSX due to security. Move along troll, and read the Mac posts too!
    4 people like this comment
    by Angry CPU February 7, 2010 8:50 AM PST
    Attackers do not target Macs because there is not much below the surface, too few users use macs to make it worth while. Attackers go after systems that do real work.
    by Random_Walk February 7, 2010 3:48 PM PST
    "too few users use macs to make it worth while."

    So millions of machines, owned by fairly affluent users, usually left on 24/7, practically none of which run anti-virus, in a homogeneous environment...

    Nah - that can't be a ripe target or anything... *rolls eyes*
    by MadLyb February 5, 2010 2:23 PM PST
    Plug-in, add-on, whatever you want to call it. You are installing it on your machine and if you just blindly trust folks like Mozilla to act as gatekeeper, then you deserve what you get.

    I would have thought people learned their lesson with toolbar debacles from a few years ago.
    Reply to this comment 4 people like this comment
    by Edonkey2000 February 5, 2010 3:25 PM PST
    I applaud firefoxwith taking this threat down. [CNET editors' note: URL removed.]
    Reply to this comment
    by finalfanoffkey February 5, 2010 3:40 PM PST
    Will that do any harm if user is logged in as non-admin? Does the install of the addon need admin right? Does that mean the firefox add-on is not more secure than ActiveX?
    Reply to this comment
    by srosenblatt February 5, 2010 3:47 PM PST
    If you have either of these add-ons, uninstall them immediately and then run a system scan with your antivirus app.

    Only the add-ons mentioned above are dangerous. Mozilla has a fairly secure process for scanning add-ons, but no system is flawless. Don't panic, but don't mess around with known infection vectors, either.
    3 people like this comment
    by The_Computer_Man February 5, 2010 4:14 PM PST
    I have been using Sothink Web Video Downloader version 5 for a little while now. The article doesn't mention that version, is it only version 4 that contains a trojan??
    Reply to this comment
    by TotallyMadeUpName February 5, 2010 5:20 PM PST
    "Sothink Web Video Downloader 4.0 and all versions of Master Filer were found to contain Trojan horse code"

    The implication is that only version 4 of the Sothink plugin is infected.
    by OccamsAftershave February 5, 2010 5:35 PM PST
    Can the add-on developers be fingered by Mozilla?
    Reply to this comment
    by Random_Walk February 7, 2010 8:38 AM PST
    Nobody uses finger on the Internet anymore
    (http://en.wikipedia.org/wiki/Finger_protocol)

    (sorry - couldn't resist :) ).
    by corelogik February 5, 2010 5:41 PM PST
    I don't use either of these add-ons. I also don't know about anyone else, but If I found out that a plug-in, add-on, whatever had any sort of attack code in it, I would never trust anything that company published again.

    If version 4 is infected, why would you trust them enough to use the next version. They have demonstrated an ability and willingness to put Trojan infected software out. Never trust them again.

    Just my $0.02.
    Reply to this comment 3 people like this comment
    by RamaSubbu_SK February 5, 2010 6:49 PM PST
    What about Microsoft Security Essential - Free antimalware application ? Has anyone tested with those ? Can it deduct these trojans ?
    Reply to this comment
    by shellcodes_coder February 5, 2010 7:54 PM PST
    This is the reason I don't install any add-ons and don't need them either!!
    Reply to this comment 1 person likes this comment
    by lordmorgul February 5, 2010 9:07 PM PST
    By the same logic you could choose to uninstall the browser entirely and simply not browse the internet at all. This is a silly conclusion to make. Threats exist... minimized their impact to you and mitigate the risks, but avoiding all possible threat sources is tantamount to putting your head in the sand and claiming everything in just like you want it to be so nothing should need changing. Sure, ok, sand in your ears is ok if you want it there. I'll use a few well chosen addons and benefit from them (while browsing more safely than you).
    2 people like this comment
    by SirWumpus February 6, 2010 12:58 AM PST
    Avria has a free AV scanner too. And Malwarebytes also has a free scanner and frankly puts many of the AV scanners to shame. Can't say enough good things about Malwarebytes.
    Reply to this comment
    by queticomn February 6, 2010 2:30 AM PST
    Norman is also free on SoftPedia.
    Reply to this comment 1 person likes this comment
    by DADSGETNDOWN February 6, 2010 6:36 PM PST
    I hope that EVERY thing by these 2 users or whoever are deleted and they should at least be banned for a long time or forever.

    Every single addon / extensions should be checked/scanned by mozilla before being able to distribute it, that DOES include every update to addons / extensions whether they are trusted or not.
    And ofcourse the periodic and random scans of the entire inventory.
    Reply to this comment
    by this1! February 7, 2010 1:07 AM PST
    did you read the article? mozilla diud and does scan everything, its just the scanning they used wasn't completely foolproofed, so they increased its scope and ability and ran it again...
    (28 Comments)
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