New Delhi, May 31 -- The Central Board of Secondary Education's (CBSE) revaluation portal was hit by a "malicious cyberattack" that disrupted payment processing for around 50 Class 12 students and forced the board to defer the next phase of its re-evaluation process until the payment system was secured, education ministry officials familiar with the matter said on Friday.

According to a senior ministry official, the payment gateway linked to the CBSE's revaluation portal was attacked shortly after the system went live on May 19.

"There were some unauthorized attacks on the portal. The malicious cyberattack affected the payment gateway infrastructure, resulting in incorrect fee displays during transactions. Around 50 students were affect...