The woman, an Iranian national, was travelling from Doha to Bali with her husband and child on a Qatar Airways flight on Sunday, Hindustan Times reported.
As her husband slept, she used his finger to unlock his fingerprint-protected phone, revealing the alleged affair in all its sordid detail.
Angered by the discovery, the woman reportedly started to hit her husband. The cabin crew intervened but were unable to calm her down.
With the inflight episode spiralling out of control, the pilots decided to make an unscheduled stop in Chennai. The woman, her husband and their child were taken off the plane, which then resumed its journey to Indonesia, an unnamed security official told the paper.
Qatar Airways was not immediately available for comment when contacted by AFP.
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