An unchecked ransomware attack on a US software company has spread rapidly to companies and organizations elsewhere, even closing hundreds of grocery stores in Sweden. Cybersecurity experts called it one of the biggest criminal ransomware attacks in history, NBC reports. Kaseya, which manages programs for companies that handle internet services for other companies, was hit first. Kaseya warned its customers, but the effects in turn spread through cloud-service providers to at least 200 organizations. Experts said it appears to be the work of REvil, a Russian-speaking ransomware gang. The FBI had said REvil was behind a cyberattack on the largest meat processing company over Memorial Day weekend. Such attacks sometimes are launched at the beginning of holiday weekends, per the AP, when IT teams for companies aren't at full strength.
A supermarket chain in Sweden, Co-op, had to close about 500 stores when checkouts stopped functioning. Swedish State Railways and a chain of pharmacies also were affected. It's an example of why concern is growing about supply chain attacks, in which hackers bring down many organizations by hitting a software supplier, per the BBC. Kaseya's chief executive said it hopes to release a patch quickly to gets its customers going again. "I've got 300, 400 people on Tuesday that are expecting to come back to work," said Alex Dittemore, founder of SoCal Computers. His company's clients were frozen by the ransomware. "It would be nice if we could get some kind of decryption key or golden bullet." The FBI and the US Cybersecurity and Infrastructure Security Agency are investigating. (Read more ransomware stories.)