Whether the motivation is trendy “hacktivism” or more traditional extortion, mortgage lenders and other financial institutions are seeing large spikes in a variety of cyberattacks these days. Prolexic Technologies, a firm that helps companies combat such assaults, said there has been an almost threefold increase in the number of attacks against its financial services clients during the first quarter of 2012 compared with the fourth quarter of 2011, along with a skyrocketing increase in malicious “packet” traffic. “During 4Q11, over 168 trillion bits of data and 14 billion packets of malicious...