The memo, which was obtained and reported exclusively by news agency Reuters, states that Anonymous was able to create multiple "back doors" to government systems, enabling the group to return repeatedly to steal sensitive data as recently as last month.
The campaign is continuing, and the memo, distributed last Thursday, warns agencies to check their systems for possible compromises. The U.S. Army, Department of Energy, and Department of Health and Human Services are among the agencies that have been hacked, according to the Reuters report.
According to an internal email from Energy Secretary Ernest Moniz' chief of staff, Kevin Knobloch, the stolen data included personal information on at least 104,000 employees, contractors, family members, and others associated with the Department of Energy, along with information on almost 20,000 bank accounts, Reuters reports.
Officials linked the attacks to the case of Lauri Love, a British resident indicted Oct. 28 for allegedly hacking into multiple U.S. government agencies via a vulnerability in Adobe's ColdFusion software, which is used to build websites.
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