The Ottawa university first posted a notice late Tuesday morning advising students of the disruption, calling it “an attempt by an external group or individual to hack into the IT network.”
Affected users were advised to refrain from accessing the network, including connecting to Wi-Fi or using a printer. They were also advised to shut down their computers.
Network users were instructed to ignore requests for payment, and report them to staff.
Ransomeware blocks legitimate users from a system and demands payment in exchange for a software code or key to regain access.
While staff and student email was unavailable Wednesday morning, the university remains open and classes are continuing.
This isn’t the first Canadian university hit by hackers — earlier this year the University of Calgary paid $20,000 to cyber attackers to halt a takeover of the the school’s email network.
The university said at the time that it had a responsibility to protect the privacy of its staff and students, and do whatever necessary to restore the accounts.
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“You’re kind of between a rock and a hard place — there is the option of not paying any ransom ever, on principle; or you pay the ransom and possibly get the appropriate means to decrypt your data,” said John Aycock, a security expert in the university’s computer sciences department, told Global News at the time.
Carleton University is posting updates on its hacking situation here.
— With files from Erika Tucker