hello, this is a scam tactic that is trying to trick you into installing malware, so don't download or execute this kind of stuff! only download firefox from its official location at mozilla.org - in addition updates are handled automatically by firefox so you don't have to download anything (you can initiate a check for updates in the firefox menu ≡ > help ? > about firefox).

you might also want to run a full scan of your system with the security software already in place and different tools like the free version of malwarebytes, adwcleaner & kaspersky security scan in order to make sure that there isn't already some sort of malware active on your system that triggers these false alerts.

Troubleshoot Firefox issues caused by malware

Thanks Philipp......I've run Malwarebytes, Microsoft Security Essentials (full scan) and neither detected the presence of malware/spyware.....wondering where it's originating from and how to rid myself of the intruder.

It just happened again.....here's the url.

https://onohzpictureme.net/7471182671240/995b4e3e470be4151009d1db507fe29f.html

please try adwcleaner as well...

Report this as "distributing modified Firefox/malware" at https://www.mozilla.org/legal/fraud-report/ and Google may block if reported enough at https://www.google.com/safebrowsing/report_phish/

According to a whois search both sites was only created recently by the same guy in Texas registering similar sites.

User's can report crap like that from right inside Firefox!

Help > Report Web Forgery... - that will capture the URL so you don't even to copy and paste it into the report page which was hyperlinked by James.

https://www.google.com/safebrowsing/report_phish/

It's still occurring....posted this on Mozilla Firefox Facebook page...

At least once a week, while using Firefox,malware "pops up" using your logo suggesting an immediate download is necessary to continue....used your new "Make Shot" from Test Pilot to capture the malware screen and would like to share it with the Mozilla team to hopefully get explanations and a remedy. Please advise as this weekly nuisance needs to stop. Thank you.

Any suggestions?

we now suspect this is coming form "malvertising" (=ads placed on legitimate websites that redirect you to this fraudulent message), so using an adblocking addon like https://addons.mozilla.org/firefox/addon/ublock-origin/ would also help with that.

I found a fake Firefox update

Did as you advised, hopefully it helps with this issue. Thanks Philipp.