The City of Tulsa is warning residents that the hackers behind a ransomware attack on its systems in May have shared sensitive files on the dark web.
The authorities said on Tuesday that the attackers have published more than 18,000 files on the dark web “mostly in the form of police citations and internal department files”.
The police citations contain personal identifiable information (PII) such as name, date of birth, address and driver’s license number, although social security numbers were not included.
The City is advising residents that anyone who has filed a police report, received a police citation, made a payment within the City, or interacted with the City in any way where PII was shared, “whether online, in-person or on paper” should take monitoring precautions. This includes monitoring financial accounts, issuing a fraud alert, and changing passwords.
“The City’s Incident Response Team and federal authorities are continuing to investigate the data breach and monitor any information being shared,” the City stated.
Following the attack in May, the City said its main priority has been restoring critical resources and mission-essential functions, which included public-facing systems and internal communications and network access functions. Business recovery teams have categorised and prioritised system restoration efforts and continued to restore and validate business systems in the City.
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The ransomware reportedly entered the City’s systems on April 21 and Tulsa Mayor GT Bynum said that city officials thought the attack shared similarities with the Colonial Pipeline attack, as reported by KTUL.
A note was sent to the City following the hack, where the hackers demanded money or they would announce the city’s system had been hacked, causing the City to announce the hack first and refuse to pay any ransom, according to KJRH.
Earlier this month, the US Department of Justice (DoJ) elevated ransomware investigations to a similar statues as terrorism, in the wake of high-profile attacks on the country. Internal guidance reportedly showed that ransomware investigations in the field should be centrally coordinated with a new task force in Washington.
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