Up to 49,000 people registered at the university may have had their details illegally accessed. The news arrives weeks after SC reported University of Colorado, in Boulder had been hit twice in two weeks.
The university only realized it had been hit for a third time when it started making improvements to its existing system.
"It was through the work we have been doing as a result of the earlier breaches that we discovered this incident," said Dan Jones, information technology security coordinator at the university. "Discovery of this computer access is a direct result of the risk assessment we are in the process of implementing, which ultimately will improve security for campus servers that contain the most sensitive data."
University investigators believe the attack probably occurred at around the same time as the two previous breaches. The data accessed contained names, addresses and Social Security numbers, but the university does not believe that any data was copied.
"The university is very concerned about computer security and we're working hard to ensure our policies and security measures promote a high degree of confidentiality," Bobby Schnabel, vice provost for academic and campus technology told local newspaper Rocky Mountain News.