The leaks occurred at opposite ends of the exam process.

In 2024, the paper was allegedly leaked after printing, when sealed trunks were opened during transit to exam centres. Investigators said the breach was limited, involving about 40-50 people, and the Supreme Court ruled the exam's overall integrity remained intact, rejecting calls for a re-test.

In 2026, the leak allegedly happened before the paper left the NTA, with teachers accused of leaking it from within the system. Officials say the safeguards on printing, transport and distribution held up. The vulnerability lay at the source, before the secure chain of custody even began.

For Prof V Kamakoti, director of Indian Institute of Technology (IIT) Madras and a member of the task force, the two episodes expose where trust in an examination system ultimately resides.

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"The roots of trust lie in two places: the teachers who set the question papers and the invigilators who supervise candidates. If either is compromised, the system is vulnerable," he told the BBC.

Officials have proposed extensive CCTV surveillance, with live feeds monitored from central control rooms. Kamakoti says AI could go further, automatically flagging suspicious behaviour - such as prolonged conversations between invigilators and candidates - so officials can intervene in real time. "At least the invigilator part we can certainly handle."

But he argues that the bigger leap in security lies in moving exams online.

Computer-based testing, he says, would make India's examinations far more secure. "Compromising the technology would be extremely difficult," he said, pointing to more than a decade of experience running large-scale computer-based examinations..