Hackers gained access to the Social Security numbers of more than two dozen people during a ransomware attack that forced the city of Tulsa to shut down parts of its computer network for months, officials said.
The hackers got Social Security numbers for 27 people in the cyberattack Tulsa detected May 6, Michael Dellinger, the city’s chief information officer, said Tuesday.
The city said in June that the hackers had gotten into files that included other personally identifiable information, such as names, birth dates, addresses and driver’s license numbers, but not Social Security numbers. But further investigation revealed more.
“As you can imagine, it takes time to thoroughly analyze every file,” Dellinger said.
Dellinger said the Social Security numbers that were hacked had been included in online police reports submitted between Jan. 1, 2015, and May 6 — when the city found out about the attack.
“While normally not included on online police reports, the team identified 27 instances of Social Security numbers being put into a free form text field” that were accessed, Dellinger said.
The city is trying to reach the 27 people whose Social Security numbers were hacked, he said. Any resident who filed a police report online can go to www.cityoftulsa.org/cyber to find out if their information was released on the dark web.
“If you received a ticket in the field, these records were not released,” according to Dellinger.
More than 18,000 hacked files were posted on the dark web with other information such as names, dates of birth, addresses and driver’s license numbers.
The city shut down its network when it discovered the hack, which primarily affected those trying to pay water bills.
All public-facing services have since been restored and the entire network is expected to be fully functional by Sept. 15, Dellinger said.
Dellinger said the city knows who was behind the hack but that the group will not be identified because it is seeking publicity.
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