I haven't heard much about this one other than what is mentioned below, but I would think this large attack is a variety of one of those fake Anti-Virus scanner 2011 RBN type of scams (randsomware) malware installs.
Slashdotted:UK PC users hit by huge fake antivirus attackQuote:
"UK Internet users were on the receiving end of a large drive-by web attack at the end of February, which attempted to push fake antivirus at least 750,000 times on a single day alone, security company AVG has said. According to a company analysis, on Sunday 27 February, detection levels for the previously obscure Russian 'Blackhole' exploit kit suddenly spiked to 900,000 globally from a few tens of thousands that would be typical for such kits, before dropping back again. Unusually, almost 750,000 of these detections were for UK PCs, which offers a baseline for what must have been a sustained attack several times that size against mainstream web servers frequented by users in the country."
Posted: Sat Mar 19, 2011 9:44 am 
