Those responsible for a ransomware attack on the city of Tulsa last month are sharing personal information of some residents online, city officials said Wednesday.
More than 18,000 city files, mostly police reports and internal police department files, have been posted on the dark web, said Michael Dellinger, Tulsa’s chief information officer.
“While we’re still investigating, some of the files contained personally identifiable information, such as name, date of birth, address and driver’s license (numbers),” Dellinger said.
He said the police reports do not include social security numbers.
Ransomware is malicious software that locks a computer and its data until a ransom is paid. Dellinger said the hackers sent the city a message asking them to contact its negotiators to discuss a payment.
“We chose not to do this,” Dellinger said.
City officials are warning anyone who has filed a police report or shared personally identifiable information with the city to monitor their financial accounts and credit reports. They are also warning those people to alert credit and debit card companies and to change passwords to personal accounts.
Last month, the city said no personal data had been accessed by the breach. The ransomware was initially detected May 6, the city said.
Tulsa shut down much of its network to stop the ransomware from spreading. The primary effect of the shutdown was that most residents were prevented from paying their water bills because the city could not process credit or debit cards with computers inoperable.
While public-facing computer systems and networks, such as those used by residents to pay utility bills or municipal fees, have been restored, it could take another two months to get all of the city’s core systems up and running, Dellinger said.
“As part of the restoration effort, the city has implemented additional security measures and increased monitoring to further protect citizens’ data from future attacks,” Dellinger said.
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