The social networking giant awarded Zonel Sougaijam $5000 (roughly about Rs. 3.4 lakh) for the discovery and also included him in the "Facebook Hall of Fame 2019" that has so far included 96 people for "making a responsible disclosure" to Facebook.
Sougaijam discovered that during a voice call on the instant messaging platform, the bug allowed the receiver to upgrade it to a video call without the knowledge of the individual making the voice call.
The bug therefore allowed people to infringe on the privacy of users. Sougaijam's discovery helped Facebook fix a big security lapse.
"In fact during a WhatsApp's video call say the other person turns his or her camera off for a reason and the video call gets paused, you can resume it without the other person even touching his or her smartphone," Sougaijam wrote in a blog post.
"I came to know it was a serious bug and I reported right away to Facebook through the Facebook's bug bounty programme where you can report bugs which poses security threat to Facebook related products.
"After few days of chatting about the bug and I also made a short video in which I explained to them how the bug is behaving. They told me that the bug was confirmed and they are working for a fix," Sougaijam, who is a Bachelor of Technology (B.Tech.) in Civil Engineering, added.
And about two weeks later, Facebook informed Sougaijam that the bug has been fixed.
"So, I checked myself and the bug got fixed," he added.
"The bounty amount is decided by the degree of severeness the bug possess, quality of the report and many other factors. The minimum amount which a person can get if his or her bug is identified as security threat is $500 which is roughly Rs 34,000," Sougaijam informed.
Sougaijam is, however, not the only Indian who has made in to the Facebook Hall of Fame 2019.
Rony K Roy and K.S. Ananthakrishna from Kerala are some of the other young Ind who have made it to the list.
Ananthakrishna detected the bug that enabled other people to completely remove files on WhatsApp without knowledge of the user.
( With inputs from IANS )