The Department of Homeland Security issued a government-wide directive to purge agency networks of potentially compromised servers after discovering the Treasury and Commerce departments were victims of a monthslong cyberattack campaign.

Last night, SolarWinds, an IT company that runs network management systems whose thousands of clients include the Department of Justice, the Census Bureau, the Department of Veterans Affairs, NASA, the Pentagon, the State Department, other federal agencies, and hundreds of companies and governments, acknowledged that its systems had been compromised.