Hackers extract $300 ransom from Medfield after ‘locking’ town network

The town of Medfield paid a $300 ransom to hackers who installed a virus that completely disabled the municipal computer network for about a week, according to town officials.

In a statement released by Town Manager Michael J. Sullivan’s office on Monday, the town disclosed that a hacker sent an e-mail infected with a “ransomware virus’” into the town’s network on Jan. 25 that became active and locked up the network.

The town turned to law enforcement, other communities that had faced similar problems, and computer experts, but no one could unlock the network. “After numerous attempts were made to unlock the town’s files, it was determined paying the ransom was the most expedient option for the town,’’ the statement said.

The town then followed the hacker’s instructions and paid out one-half of a bitcoin, valued at $300, as demanded by the hacker. “Once the ransom was paid, the hackers provided the town with a software key to begin the process of unlocking the files,’’ he wrote.

After reviewing the system, the town concluded that a data breach did not occur and that no files were removed from the network. The town said payroll records are kept off-site with a payroll vendor and “department information and records” are stored on a different server.

The network was restarted Monday. “The town is still in the process of rebuilding some areas of the network,’’ officials said. The town is also backing up files and looking for ways to better protect its network.