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A username and password are being requested by http://check-work-12989.top. The site says: "Firefox Update Error 0x09009388 Help Desk: +1 (855)*** (TOLL-F

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  • Last reply by philipp

xyyy
xyyy
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Hello Whenever I open Firefox, a window with address "data:text/html;base64,PCFER0NUWVBFIG"... there's more but I cannot see it all and the quotation marks (") are mine. A voice comes on telling me that my computer is infected, etc and in the centre of the window is the following: "A username and password are being requested by http://check-work-12989.top. The site says: "Firefox Update Error 0x09009388 Help Desk: +1 (855)*** (TOLL-FREE)"" and it asks for my username and password. How do I get rid of this? Thank you.

edit: removed malicious phone number (philipp)

Hello Whenever I open Firefox, a window with address "data:text/html;base64,PCFER0NUWVBFIG"... there's more but I cannot see it all and the quotation marks (") are mine. A voice comes on telling me that my computer is infected, etc and in the centre of the window is the following: "A username and password are being requested by http://check-work-12989.top. The site says: "Firefox Update Error 0x09009388 Help Desk: +1 (855)*** (TOLL-FREE)"" and it asks for my username and password. How do I get rid of this? Thank you. <sub>edit: removed malicious phone number (philipp)</sub>

Modified by philipp

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philipp
philipp
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hello, this sounds like an issue with malware on your system displaying this fraudulent message. please perform all these steps:

  1. refresh firefox (this will keep your bookmarks and passwords)
  2. afterwards go to the firefox menu ≡ > addons > extensions and in case there are still extensions listed there, disable them.
  3. finally run a full scan of your system with different security tools like the free version of malwarebytes and adwcleaner to make sure that adware isn't present in other places of your system as well.

Troubleshoot Firefox issues caused by malware