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35.174.25.43 is blocking me out of Firefox, asking for username and password and asking to call 1.855.xxx.xxx.

  • 2 replies
  • 1 has this problem
  • 7 views
  • Last reply by FredMcD

Sailmaker
Sailmaker
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I opened Firefox on my laptop,, a Microsoft window appeared with a pop up box labeled “ Authentication Required “ and states “ http:35.174.25.43 is requesting your username and password. The site says: “Suspicious activity detected on your IP address due to harmful virus installed in your computer Error: Unknown System Failure! Call Toll Free now ++1...”. The number, 1-855-xxx-xxx is in bold in the right hand upper corner of the page. I called it. A man claiming to be with a company contracted by Microsoft to support Mozilla answered the phone after I interrupted him and demanded that he identify exactly who he was and what company he worked for. I ended the call and told him I would call back later. (Obviously, I did this so I could verify/investigate). He called me back in 5 minutes from 877.xxx.xxxx and said he would call me back at “ a more convenient time later”. My questions are: What in Hell is going on here? Is this legitimate?

I opened Firefox on my laptop,, a Microsoft window appeared with a pop up box labeled “ Authentication Required “ and states “ http:35.174.25.43 is requesting your username and password. The site says: “Suspicious activity detected on your IP address due to harmful virus installed in your computer Error: Unknown System Failure! Call Toll Free now ++1...”. The number, 1-855-xxx-xxx is in bold in the right hand upper corner of the page. I called it. A man claiming to be with a company contracted by Microsoft to support Mozilla answered the phone after I interrupted him and demanded that he identify exactly who he was and what company he worked for. I ended the call and told him I would call back later. (Obviously, I did this so I could verify/investigate). He called me back in 5 minutes from 877.xxx.xxxx and said he would call me back at “ a more convenient time later”. My questions are: What in Hell is going on here? Is this legitimate?

Modified by James

Chosen solution

hi, this is not legitimate and will be caused by malvertising on sites you visit that redirect you to these fraudulent pages claiming they detected something malicious on your system (in fact that's not possible to do for a website). do not call any of the displayed phone numbers or react to calls you might receive from them.

Avoid and report Mozilla tech support scams

edit: using an adblocking addon like https://addons.mozilla.org/firefox/addon/ublock-origin/ might get rid of such nuisances in the future,

Read this answer in context 👍 0

All Replies (2)

philipp
philipp
  • Moderator
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Chosen Solution

hi, this is not legitimate and will be caused by malvertising on sites you visit that redirect you to these fraudulent pages claiming they detected something malicious on your system (in fact that's not possible to do for a website). do not call any of the displayed phone numbers or react to calls you might receive from them.

Avoid and report Mozilla tech support scams

edit: using an adblocking addon like https://addons.mozilla.org/firefox/addon/ublock-origin/ might get rid of such nuisances in the future,

Modified by philipp

FredMcD
FredMcD
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. Whenever you get a message / popup like that;

DO NOT USE ANY OF THE PROVIDED LINKS OR ANY PHONE NUMBERS ! !

Such messages are only Spam that could lead you to Fake Support. Not only can they damage or hack your system, they charge you to do so.

You may have ad/mal-ware. Further information can be found in this article; https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware?cache=no

Run most or all of the listed malware scanners. Each works differently. If one program misses something, another may pick it up.