Pop-up window with an attempt to open a URL - has anyone seen this?

I've seen it, and it's just a pop-up add designed to fool you into downloading some malware. Close it and ignore it. Even if you have pop-up blocking turned on, you can still get them, since they're activated by Flash and JavaScript. The only way to prevent all of them is to disable JavaScript and Plugins in Safari preferences.

Mulder

so is there no threat from this site, other than just being a nuisance? and I am hoping safari does not download anything automatically, although I should've seen the download window open in that case.

There is no threat from that window; it is merely a nuisance. Safari doesn't download anything automatically, and even if it did, installing anything requires user authorization.

Mulder

Even if did download something (which it didn't), nothing can get installed without your say-so.

I got this this morning.
It popped up if you go on surfline.com. Looks like they have pirated that domain. It loops you and you can not get out unless you force quit safari.
Tried to close out and it opened a page that 'scanned' my hard drive and told me I had 44 viruses.
you click clean or cancel, if you click cancel, it says something like, if you cancel you will crash your hard drive, or some such nonsense.
Looks like microsoft/norton, very convincing.
It also downloaded an application.
Nasty little thing.
I just quit safari, then dumped the app in the trash, and reset all safari.
we'll see.
I don't have any virus protection on my computer.
Time to go to the apple store.
Another reason to feel sorry for pc users.

Mac OS X 10.4 Tiger automatically checks your downloads for malicious software and content that could harm your system or collect information from your computer. You can read more about that here:

http://support.apple.com/kb/HT2340

If you feel you need added protection, read on:

SecureMac has introduced a free Trojan Detection Tool for Mac OS X. It's available here:

http://macscan.securemac.com/
The DNSChanger Removal Tool detects and removes spyware targeting Mac OS X. Called DNSChanger Trojan and also known as OSX.RSPlug.A Trojan Horse, the software attacks users attempting to play a fake video file.

Upon attempting to play the video, the victim receives the following message:
“Quicktime Player is unable to play movie file.
Please click here to download new version of codec.”
Upon running the installer, the user's DNS records are modified, redirecting incoming internet traffic through the attacker's servers, where it can be hijacked and injected with malicious websites and pornographic advertisements. The trojan also installs a watchdog process that ensures the victim's DNS records stay modified on a minute-by-minute basis.
SecureMac's DNSChanger Removal Tool allows users to check to see if the trojan has been installed on their computer; if it has, the software helps to identify and remove the offending file. After a system reboot, the users' DNS records will be repaired.

There may be other ways of guarding against Trojans, viruses and general malware affecting the Mac. A white paper has recently been published on the subject by SubRosaSoft, available here:

http://www.macforensicslab.com/ProductsAndServices/index.php?mainpage=document_general_info&cPath=11&productsid=174

Also, beware of MacSweeper:

MacSweeper is malware that misleads users by exaggerating reports about spyware, adware or viruses on their computer. It is the first known "rogue" application for the Mac OS X operating system. The software was discovered by F-Secure, a Finland based computer security software company on January 17, 2008

http://en.wikipedia.org/wiki/MacSweeper

On June 23, 2008 this news reached Mac users:

http://www.theregister.co.uk/2008/06/23/mac_trojan/

More information on Mac security can be fund here:

http://macscan.securemac.com/

More on Trojans on the Mac here:

http://www.technewsworld.com/story/63574.html?welcome=1214487119

The latest news on the subject, from July 25, 2008, is:

Attack code that exploits flaws in the net's addressing system are starting to circulate online, say security experts.
The code could be a boon to phishing gangs who redirect web users to fake bank sites and steal login details.
In light of the news net firms are being urged to apply a fix for the loop-hole before attacks by hi-tech criminals become widespread.
Net security groups say there is anecdotal evidence that small scale attacks are already happening.
Further details here: http://news.bbc.co.uk/2/hi/technology/7525206.stm

You should also read what a major contributor called tacit has to say here:

http://tacit.livejournal.com/238112.html

Since Nov 5th I am having this Antivirus powerfulllivescan 2009, that re-orient my Google searches to this Antivirus 2009 web page. My google maps links (to my website) are also reacting and beeing re-oriented to this page. I have scanned my system with ClamXav (the "best" antispyware for Mac), and nothing....(Can´t open the folder with Safari chaches that have this malware 1312183484-409355674.cache)
I have used a Bitdefender 1.9 version for Mac, that recognizes this virus as AdWare.FakeAntivirus.M a recent malware. It can´t do nothing to stop it.
So here I am, waiting and searching for any news on how to kill this dangerous Mac infection.
Mac has also viruses, but I was not aware of it, and now I am infected.

When folks tried to come to one of my websites via Google link, they would get redirected to this Antivirus malware page instead. The problem was a malware file in the website folder on my web server vendor's computer. I'm not at all sure how the file could have gotten there, since I'm the only one with ftp access and my computers are Macs and I don't run Windows on them.