Staff and administrators at Prior Lake City Hall spent nearly four days battling a computer virus that struck the city’s HVAC system on the evening of Wednesday, June 8.
City Manager Frank Boyles said a subsequent internal investigation showed no evidence of a data breach of personal information, such as the city’s utility billing data.
The virus did, however, cost the city between $10,000 and $15,000, not including lost staff time. The city has insurance through the League of Minnesota Cities for data security breach expenses.
Don Uram, finance director, said the city’s IT staff spent more than 85 hours tracking down the source of the virus, securing computers at City Hall, tracking down a program to fix the problem, cleaning files and restoring servers. The virus may have been of the “Cryptolocker” ransomware variety, but “it didn’t have the characteristics of a typical one,” Uram said.
By Monday, the majority of computers were clean and file servers were restored, but it’s possible some files were lost, Uram said. The city’s financial software and police department servers did not appear infected. The virus slowed down production at City Hall, making some tasks impossible, including preparing agenda details for a workshop on Monday.
The incident has city leaders planning to use a consultant to look deeper into City Hall firewalls and any vulnerabilities within the system. Police Chief Mark Elliott said ransomware viruses and hackerware typically target governmental agencies.