UNAM investigates possible cheating in first online entrance exam

In short: UNAM is reviewing its first remote online entrance exam after experts flagged unusual scores and estimated large-scale cheating, including possible AI use.

What happened

UNAM, Mexico’s largest public university, held its undergraduate entrance exam online and from home for the first time in 2026. Around 158,000 people took the test. The exam used AI proctoring, which is software that watches test takers through a webcam and tries to spot cheating (like a digital invigilator).

After results came out, several patterns looked strange. Reports said the share of “excellence” level scores jumped from about 9% in 2025 to around 30% in 2026. There were also more perfect or near-perfect scores than expected, including in highly competitive programs like Medicine and Engineering.

Raúl Rojas, a mathematician and AI expert, analyzed the score patterns and timing data and said the results suggest that almost half of students may have cheated. That would be roughly 75,000 tests, but it is an outside estimate, not UNAM’s official number. UNAM has so far annulled about 2% of exams for rule violations.

UNAM has paused parts of the admissions process while it investigates. It also created a 16-person expert commission to review what happened and recommend next steps, which could include validating scores, canceling more exams, or redoing the test, possibly in person. On July 3, UNAM filed a criminal complaint tied to alleged fraud and paid “exam support” services.

Why it matters

Entrance exams decide who gets a seat at a public university. If cheating was widespread, honest students may have lost places. The case also raises a broader question for schools everywhere, which is whether online, at-home exams can be secured when tools like ChatGPT can answer questions quickly.

Source: NYTimes