The hacks came as students and parents attempted to access the websites at the end of this year's national college entrance examination, the Shanghai Evening Post reported Wednesday.
Hackers attacked the websites of Shanghai University of Engineering Science, Shanghai Jiao Tong University and Fudan University, authorities said.
Qihu360, a leading Chinese company specializing in Internet security, reported the average website security scores for domestic universities came in at about 55 points out of 100, while about two-thirds of the university websites failed security checks.
Hackers are reported to have attacked college websites 113 times a day on average in June, an increase of more than 20 percent compared with previous data.
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