When I was prompted to download an update to my flash player recently I did so and from that point on was plagued by the rogue search engine Delta. I also found Web Cake, BrowserProtect. It appears that the malware came from the same source as the adobe flash update. I'm still not sure I have got rid of the effects and may have to re-build my system. Was this not really Flash but as the tag below suggest, but malware_masquerades_as_flash_install?
There were dozens of reports recently about fake update notifications, trying to trick users into downloading malware.
Make sure that the download only comes from the adobe.com domain.