The Clark County School District (CCSD) in Las Vegas reopened on August 24 for in-person learning. The attack was first reported three days later by hackers in an incident recorded by the Wall Street Journal.
On the morning of August 27, according to the statement, some of CCSD’s computer systems became infected with a virus, which restricts access to certain files. The Wall Street Journal reports that authorities published documents containing social security numbers, student grades and other personal information from CCSD students and staff after the district refused to provide a ransom in exchange for unlocking computer servers.
According to CCSD, the school district currently serves more than 320,000 students in Clark County, Nevada.
CCSD did not specify whether confidential information was published, but did not accept “that some current and former employee information may have been accessed or acquired by an unauthorized actor.”
According to the statement, the school district immediately informed law enforcement, including third-party forensic investigators to look into the incident. Investigators concluded that CCSD was the victim of a criminal ransomware attack.
According to the statement, the school district is working to restore all systems to secure full functionality.
CCSD is not the only district to become a victim of cyber attack in the new year.
Hartford Public Schools in Connecticut postponed in-person classes and online learning at the beginning of the school year citing an individual ransomware virus, causing a system shortage in network infrastructure.
And the Miami-Dade School District saw dozens of attacks early in the academic year.
The juvenile’s computer and gaming system was taken into evidence, Miami-Dade School Police Chief Edwin Lopez said, adding that it is unclear whether the student was working alone.
Authorities say they believe there are other attackers. Some of the IP addresses involved in the attacks have been traced to Russia, Ukraine, China and Iraq, Superintendent Alberto Carvale said. It is unclear whether those countries are physically invasive, but school officials said they are working with international authorities in their investigation.
CNN’s Christina Maxoris and Artemis Moshtaghian contributed to this report.