Files on city computer systems have been encrypted, according to a ransom note that demands payment in bitcoin.
City officials in Atlanta are dealing with a cyberattack that uses ransomware to hold internal computer systems hostage.
The attack caused outages on several computer systems, including online bill paying services and some law enforcement data, CBS affiliate WGCL-TV reported Thursday. A ransom note discovered Thursday morning stated that all files on affected systems had been encrypted and demanded payment in the cryptocurrency bitcoin to decrypt them.
Ransomware is malicious software that can lock up your files until you send hackers a ransom payment. It featured in the WannaCry attacks in May and the NotPetya attacks in June, both of which swept through hospitals, banks and governments in several countries. But after July, the rates of ransomware infections dropped sharply, according to a report from Malwarebytes in January.
Atlanta Mayor Keisha Lance Bottoms told CBS News the city is receiving assistance from the FBI, Department of Homeland Security, Microsoft and Cisco Security.
It wasn't immediately clear if personal information had been compromised, but authorities are encouraging city employees to be on the lookout for signs that their data may have been stolen, like unexpected credit card charges.
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