The Clinton Foundation and the Democratic National Committee (DNC) were a few of the organizations breached by suspected Russian hacker group Guccifer 2.0. The hackers siphoned data for about seven month from at least 4,000 individuals associated with U.S. politics such as party aides, advisers, lawyers and foundations. 

This latest hack

Source: Hot Hardware – Russian Hacker Group Guccifer 2.0 Allegedly Pwn Clinton Foundation Exposing Large Contributions