San Jose State University officials are denying a computer hacker’s claims he stole a wealth of sensitive personal data from its largest student-run campus enterprise.

Monday, a hacker going by “S1ngularity” announced via Twitter that he infiltrated a server for the Associated Students of SJSU, a student-run nonprofit that oversees a host of campus services. It is separate from the university, with its own IT infrastructure, meaning no school data was affected.

The university acknowledged an intrusion occurred but has not corroborated the hacker’s boasts of posting information like students’ Social Security and driver’s license numbers.

“We have no evidence to suggest that the claims are accurate, but we take these claims seriously and will continue to look into the situation,” university spokeswoman Pat Harris said.

New York-based data security firm Identity Finder plucked the announcement from the obscurity of Web forums and alerted media organizations, saying it analyzed nearly four gigabytes of unencrypted data the hacker posted, including email addresses, passwords, and perhaps most disturbingly, 10,000 Social Security numbers.

Aaron Titus, the firm’s chief privacy officer, said the numbers were valid but not accompanied by names.

The university reached a similar conclusion.

“We have found no evidence to suggest (Social Security numbers) have been compromised,” Harris said.

According to Titus, the hacker employed an SQL injection that “tricked” the server into releasing the information, which he said spans the past 10 years and also includes administrative materials such as event registrations, job applications and work schedules.

Harris said the school’s Internet security team is probing the breach and noted that much of the data purportedly taken is not typically collected by the Associated Students. Other snippets of data posted on the Web are not security risks, like user names from a 2003 silent auction, she said.

“We’re pretty certain we have not compromised any sensitive information,” Harris said.

A motive for the purported hack was not immediately clear. At best, Titus said, the acts are done to expose security vulnerabilities, and at worst accompany criminal activity like identity theft.

Contact Robert Salonga at 408-920-5002. Follow him at Twitter.com/robertsalonga.