A Google Webmaster Help thread has reports that a Yahoo Domain/Hosting parking service seems to have triggered Google and Google Chrome to display a malware warning.
The user said his parked domain from Yahoo shows in Google Chrome as showing a "malware warning." He added, "there's content from geocities.com (!). How do I get ride of this and clean it up?"
True, there was/is content from GeoCities, which is a closed down property, on that site.
Google's John Mueller made it sound like the malware warning was a Google issue. He wrote:
Thanks for posting. I also brought this up with teams on our side, and it looks like we were able to tweak something there. At any rate, it looks like the message is gone, so you should be all set now :)
Forum discussion at Google Webmaster Help.