India’s Central Board of Secondary Education (CBSE) said it has contained vulnerabilities in its online grading portal after a teenage cybersecurity researcher warned that the system could have allowed unauthorized access to examiners’ accounts and possible manipulation of grades.

The issue gained national attention after students claimed the scanned answer sheets provided for reevaluation did not match their original handwritten submissions. Teen researcher Nisarga Adhikary said he had reported five critical flaws in the OnMark grading platform to the country’s Computer Emergency Response Team in February, but received only an acknowledgment before publicly disclosing his findings in May.

CBSE said cybersecurity experts from government agencies and leading engineering institutions have strengthened the platform and moved it to a more secure setup, insisting no security breach had occurred. The controversy has intensified scrutiny of India’s digital education infrastructure and prompted opposition leaders to call for an independent investigation into the grading system’s management.