I uninstalled Flash Player according to these instructions. And rebooted the computer.
The message from update-pro.org is not showing up at this point.
FWIW: The message would show up when looking at these pages:
So far, I haven't missed Flash.
Even with flash removed, when I go to the wunderground web pages the dialogues warning of Flash being out of date.
I set up a second MacBook with the same OSx and Safari. It is not having the problem with the false flash update windows.
However my original MacBook is still will see the update dialogs and, so far, only on the wunderground pages. I've been to other sites.
It is now 12 hours later. My computer was off for that period and I am now in Fiji.
The malware dialogue I was getting no longer shows up.
Consider that the two sites I was getting the error message from appear to be CDNs (content delivery networks) I am hypothesizing that someone hacked those sites rather than any particular malware being installed on my computer. Call me "Herman Cain" I have no evidence to back this up.
Flash Player is not delivered from liveupdate.upgrade-pro.org and the file name you posted is also not a valid Flash Player installer (the screenshot is also not a screenshot of a valid installer, although it's very, very close). If you have the entire URL for this site, please message it to me and I will forward it to our fraud department to follow-up on. Adobe does actively go after malicious sites who distribute fake/malicious installers.
This is one of them. There are others. Be careful, it will take over your web browser.
You will have to quit your browser and disconnect from the internet to get it to stop showing up.