Shares of television broadcaster Sinclair Broadcast Group (SBGI) - Get Sinclair Broadcast Group, Inc. Class A Report fell Monday after the company announced that it was the victim on a ransomware attack that it discovered over the weekend.
Baltimore-based Sinclair on Saturday identified and began investigating the security incident. On Sunday, the company identified that certain servers and workstations were encrypted with ransomware.
Sinclair shares on Monday closed 2.9% lower to $26.58.
The company said that it is also working to determine what information was taken from the company's network during the attack.
Sinclair says it has notified law enforcement and other governmental agencies and has engaged legal counsel, an unnamed cybersecurity forensic firm and "other incident response professionals."
The company says the event has caused, and may continue to cause, disruption to parts of its business, including aspects of local advertisements by its local broadcast stations on behalf of customers.
The company says it is working diligently to restore operations quickly.
Ransomware attacks involve an illicit actor infecting the target's network with a virus and encrypting the information contained on the network. The hackers then ransom the company's data back to them
Earlier this summer, T-Mobile (TMUS) - Get T-Mobile US, Inc. Report said more than 53 million people were hit by a data breach that included social security numbers, birth records and driving license details.
In a separate attack, hundreds of companies were directly hit by the supply-chain attack on Kesaya's VSA software, which provides IT services to small and medium-sized businesses, according to CNET. At least 36,000 companies were indirectly impacted.
The $70 million ransomware demand was posted to a dark-web blog typically used by REvil, the Russia-linked cybercrime gang behind the attack that crippled the U.S. operations of meat processor JBS Meat (JBSAY) .