Tipped off by an online hacker, applicants to several of the nation’s top business schools, including Harvard Business School (HBS), could access internal files on the schools’ websites and ascertain their admissions status a month early.

The admissions websites were vulnerable for over nine hours yesterday before the hacker’s instructions and the admissions letters were taken down.

But during the narrow time window, according to a thread on Business Week Online’s technology forum, several applicants managed to follow the hacker’s directions and read the admissions office’s response letter.

HBS requires students to submit their applications and recommendations electronically using ApplyYourself, an online application and decision notification system.

An anonymous hacker known as “brookbond,” who defined himself as a male who specializes in information technology and software security, posted the instructions on Business Week Online’s technology forum at 12:15 a.m., early yesterday.

“I know everyone is getting more and more anxious to check [the] status of their apps to HBS,” he wrote. “So I looked around on their site and found a way.”

Steven R. Nelson, executive director of HBS’s Master of Business Administration (MBA) program, said the letters were taken off the site early yesterday.

“These were just internal administrative devices,” Nelson said.

Len Metheny, chief executive officer of ApplyYourself told The Crimson that his company notified the half-dozen schools that were affected and put them on alert yesterday morning.

“The problem has been resolved since 9:45 this morning,” he said. “We made some changes to the system to prohibit access to that information.”

Metheny also noted that individuals could only access their own personal admissions responses—not those of other applicants.

Business Week officials set out to expunge the hacker’s comments from the website yesterday morning, said Kimberly Quinn, Business Week’s director of communications.

“As soon as we were informed of the situation, we deleted the post immediately,” she said. “And any other directions that anybody else posted...we deleted those right away, too.”

Nelson said HBS and Business Week did not contact each other about taking the posts down.

Before the online discussion on Business Week’s forum was deleted, other students reported that they had also accessed admissions decisions from MIT’s Sloan School of Management, the Stanford Graduate School of Business, and Duke University’s Fuqua School of Business.