Hackers aligned with Russia's government breached US Democratic National Committee computers and stole data including a trove of opposition research on Republican presidential hopeful Donald Trump, the Washington Post reported Tuesday.
The cyber-attack was so comprehensive, including one access to the DNC network that lasted the course of an entire year, that the intruders were able to read all email and chat traffic on the committee's system, DNC officials and security experts said, according to the daily.
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A computer cleanup operation this past weekend expelled the hackers from the system, the officials and experts said, and no financial, donor or personal information appeared to have been compromised, the Post said.
The security firm that conducted the cleanup, CrowdStrike, said Tuesday on its website that they received a call from the DNC to respond to a suspected breach uncovered in April.
The firm said it quickly identified "two sophisticated adversaries on the network" including COZY BEAR, which CrowdStrike said successfully hacked into unclassified networks of the White House and State Department.
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