A ransomware attack orchestrated two days before Thanksgiving has forced the Baltimore County Public School System to be shut down.
Online classes for 115,000 students were disrupted as a result of what school officials are calling a “catastrophic attack on our technology system.”
While specific details of the attack have not yet been shared, The Baltimore Sun reports that the school board meeting video stream dropped out suddenly toward the end of Tuesday night.
Teachers entering grades into the school system's computer system said on social media that they began experiencing technical difficulties at around 11:30 pm Tuesday.
The district's website, email system, and grading system have all been impacted by the incident. It is not yet clear whether any student data was exposed to unauthorized third parties.
School officials said on social media that files that were encrypted in the incident have a .ryuk extension, suggesting that Ryuk ransomware has been used by the attackers. This suggestion has not been confirmed by authorities or local officials.
Officials kept their comments on the incident to a minimum, confirming that an attack took place, that an investigation has been launched into it, and that the school system is working with state and federal law enforcement and the Maryland Emergency Management Agency.
Baltimore County Police Chief Melissa Hyatt told the Baltimore Sun simply that "we are in the preliminary steps of that investigation."
Schools in the county were closed for students today and will remain so tomorrow. However, school offices are being kept open to help staff find a way to keep teaching students whose education has already been fundamentally altered by the outbreak of COVID-19.
In a tweet, the school system said that keeping offices open will provide "much-needed time for our staff to continue working to set up the instructional platform and to communicate next steps regarding devices."
Superintendent Darryl L. Williams was unable to confirm when online classes will be able to resume.
The incident follows a number of ransomware attacks on school systems in the United States, including a September attack on the Fairfax County Public School System in Virginia.