San Diego Unified School District notified families of all its roughly 100,000 students Tuesday about a data breach of its student information system provider. PowerSchool, which is headquartered in Folsom and used by districts across the country, became aware of the incident on Dec. 28. The letter San Diego Unified sent to families said the district learned of it Tuesday. “We have been informed that some student data from our district and other districts was downloaded by an unauthorized user, and an analysis is being done by PowerSchool on the type of information accessed,” W. Drew Rowlands, the district’s deputy superintendent of operations, wrote in the email to families. Rowlands wrote that PowerSchool had informed them that the situation had been contained. District spokesperson James Canning wrote in a Wednesday email that families of all current students were sent an email, and they have about 115,000 emails of current students. He wrote there are nearly 99,000 students in the district. PowerSchool said in a statement Wednesday that it had become aware of a potential incident where an unauthorized user gained access to certain information through a consumer portal. “We have taken all appropriate steps to prevent the data involved from further unauthorized access or misuse,” a spokesperson wrote. “The incident is contained and we do not anticipate the data being shared or made public. PowerSchool is not experiencing, nor expects to experience, any operational disruption and continues to provide services as normal to our customers.” The company said it had immediately engaged its cybersecurity response protocols and mobilized a response team, which included senior leadership and third-party cybersecurity experts. Rowlands said San Diego Unified would notify families with further updates as it learned more. Canning said that only students would have been impacted, and no immigration status information would have been included. County officials couldn’t immediately say if other schools in San Diego County were affected. San Diego Unified had previously notified families of a data breach in 2023, but Canning said that breach involved the district, not a vendor.