Sirefef. How to remove?
(Uninstall guide)

Sirefef is also known as Trojan.Sirefef,, sirefef.b, win32/sirefef, win64.sirefef | Type: Trojans
Severity scale:  

Sirefef is a Trojan family that includes different types of parasites, which does different things. Every version has it’s own task, like one component opens all firewall blocks, another downloads malicious files and updates from the internet, then the other tries to hide them all from the system. Some other versions redirect web traffic generate pay-per-click traffic and show annoying pop ups.

It is very important to remove Trojan Sirefef from your computer, because it may not only use your computer and internet resources for illegal purposes, but it can also delete files on your system, find sensitive information, like passwords, financial information and send them to a remote server, where cybercriminals can use them. Additionally it may open a remote control connection to your PC.

If you will not remove Trojan Sirefef from your PC, it will continue to change your registry settings and other important windows files, which might cause your computer crash. Additionally, it will make your computer much slower, and you might find it difficult to browse the internet,
or use search engines, to find information.

Sirefef in PPC results in Bing and Yahoo

Microsoft does not look enough to their paid results and Yahoo shows paid results from Bing. Guys at GFI labs cought Sirefef in their PPC results. If you would search for adobe flash player in Bing and Yahoo,  you would get these results some time ago. They look innocent, but if you try to get the flash update from there (in this case from, you would be redirected to page which looks like a page to get flash.

Sirefef in Bing paid results

The page you will land looks like official page from Adobe, where you can get the updates. The small difference is that it is not a page from Adobe. It redirects to a directory on fake site, downloading a file from torreandaluz (dot) com/flash/Flash Player 10 Setup.exe. After checking this file on, GFI found Sirefef.

fake flash update

How to get rid of Sirefef virus?

Sirefef kills any attempt to remove it, and is nearly impossible to clean. Luckily antispyware developers found the way to delete Sirefef trojan for the PC system. Bad news is that manual removal instructions will not work, as Sirefef mutates, but you can use automated solution. For removal of Sirefef trojam we advise to use SpyHunterSTOPzilla or Malwarebytes Anti Malware.

Automatic Sirefef removal:

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remover for Sirefef
Compatible with OS X
Webroot SecureAnywhere AntiVirus is recommended remover to uninstall Sirefef. You should confirm using free trial that it detects current version of parasite.
Not using OS X? Download a remover for Windows.
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remover for Sirefef Happiness
Compatible with Microsoft Microsoft Windows logo
SpyHunter is recommended remover to uninstall Sirefef. You should confirm using free trial that it detects current version of parasite.
more than 40.000.000 downloads!
What to do if you failed to remove the infection?
If you failed to remove Sirefef using Webroot SecureAnywhere AntiVirus SpyHunter, read here how to submit a support ticket or submit a question to our support team and provide as much details as possible.
Alternate Software
We are testing STOPzilla's efficiency at removing Sirefef (2012-05-16 09:14:15)
Malwarebytes Anti Malware
We are testing Malwarebytes Anti Malware's efficiency at removing Sirefef (2012-05-16 09:14:15)
XoftSpySE Anti Spyware
We are testing XoftSpySE Anti Spyware's efficiency at removing Sirefef (2012-05-16 09:14:15)
Zemana Antimalware
Virus Removal Phone Support
Help Line to remove Sirefef
Sirefef screenshot
Sirefef snapshot

Sirefef manual removal

Kill processes:
Unregister DLLs:

Delete files:

Geolocation of Sirefef

Map reveals the prevalence of Sirefef. Countries and regions that have been affected the most are: Spain, Canada, Italy, Germany and United States.

Removal guides in other languages

Information added: 09/24/13 07:01; information updated: 09/24/13 07:01

Additional resources

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Comments on Sirefef

malwarebytes did not find it at found trojans and some other thingy...i went to and downloaded thier free one and it found sirefef and got rid of it in no time.
Mike in IT
Malwarebytes didnt even detect it. We have Forefront and it gets detected, but after removal it just comes right back in only a couple of minutes.
i cant access the internet, probably because of the virus. Can i download spyhunter in safe mode

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