After a record-low of four million in the 2011 Verizon Data Breach Investigations Report, the number of compromised records skyrocketed back up to 174 million in this year's report – which puts 2011 in second-place for the highest data loss since the report began in 2004.

The most likely threats involve authentication attacks and failures, continued espionage and “hacktivism” attacks, Web application exploits and social engineering, the report states.