The firefox-patch.js is not the cause of the fake urgent Firefox updates sites but is what these sites try to convince inexperienced Windows and or Firefox users to download and run without scanning first.
If you did run the firefox-patch.js on Windows then you may want to try and do some cleanup.
You can try these free programs to scan for malware, which work with your existing antivirus software:
Microsoft Security Essentials is a good permanent antivirus for Windows 7/Vista if you don't already have one. Windows 8/10 have antivirus protection built-in.
Further information can be found in the Troubleshoot Firefox issues caused by malware article.
The firefox-patch.js is not the cause of the fake urgent Firefox updates sites but is what these sites try to convince inexperienced Windows and or Firefox users to download and run without scanning first.
If you did run the firefox-patch.js on Windows then you may want to try and do some cleanup.
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You can try these free programs to scan for malware, which work with your existing antivirus software:
* [http://www.microsoft.com/security/scanner/default.aspx Microsoft Safety Scanner]
* [http://www.malwarebytes.org/products/malwarebytes_free/ MalwareBytes' Anti-Malware]
* [http://support.kaspersky.com/viruses/disinfection/5350 Anti-Rootkit Utility - TDSSKiller]
* [http://general-changelog-team.fr/en/downloads/viewdownload/20-outils-de-xplode/2-adwcleaner AdwCleaner] (for more info, see this [http://www.bleepingcomputer.com/download/adwcleaner/ alternate AdwCleaner download page])
* [http://www.surfright.nl/en/hitmanpro/ Hitman Pro]
* [http://www.eset.com/us/online-scanner/ ESET Online Scanner]
[https://support.microsoft.com/help/14210/security-essentials-download Microsoft Security Essentials] is a good permanent antivirus for Windows 7/Vista if you don't already have one. Windows 8/10 have antivirus protection [https://www.microsoft.com/windows/windows-defender built-in].
Further information can be found in the [[Troubleshoot Firefox issues caused by malware]] article.