ROCKFORD, Ill. (WTVO) — On Wednesday, Rockford Public Schools shared details about a devastating cyber attack the district suffered in September.

The district continues to recover from the ransomware attack, a computer-based attack in which hackers install software on a remote computer system that encrypts files so the owners cannot access them without paying a ransom.

According to a post on the RPS District 205 website, around 10 p.m. on Thursday, September 5th, the network was attacked by 199 variants of a virus which its antivirus security protocol could not keep up with.

Around 10 p.m., 50 to 60 of the roughly 300 servers went down in rapid succession. Executive Director of Technology Jason Barthel disconnected the network from the Internet at midnight, but the damaging programs were already installed and replicating within the computers attached to the network.

“I don’t want to scare anyone or make people uncomfortable. But this is an epidemic. It’s a serious global issue. This isn’t someone sitting in a basement with a grudge against RPS 205. This is organized crime,” he said.

“We can’t share many details of this specific attack on RPS 205, because it’s part of an ongoing investigation. But the easiest and most common way to get a username and password is to send an email with malicious items and trick a person into clicking on an email or downloading what appears to be a safe PDF. If you’re clicking on and downloading things daily, you might lose your sense of cautiousness, and some of the phishing emails look very sophisticated. A virus can install on a device with one click. Depending on that user’s access level, it can spread like wildfire,” Barthel continued.

The district says there is no evidence that personal information of students or staff was downloaded by the hackers; the attack meant only to cripple the system by blocking users’ access to computer data.

In the resulting two months, the district has worked to rebuild 5,000 computers, 300 servers, and 1,200 wireless access points, and expect computers to be returned to all teachers by mid-November.

The school says the next step includes purchasing new devices to replace old desktop and laptop computers by the coming Spring, for a total of $3.1 million.

The school district has also released a podcast detailing the effects of the outage.

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