WhatsApp has reportedly fixed a bug that could've given hackers control of a user's app through video calls.

The maker of the chat app released a fix for the iOS version on Oct. 3 and updated the Android version on Sept. 28. Hackers could've seized a user's WhatsApp when he or she answered an incoming video call, according to CNET sister site ZDNet.

A security researcher at Google's Project Zero reportedly discovered the flaw in August. The "memory corruption bug" affected WhatsApp's use of Real-Time Transport Protocol for video calls, ZDNet said. RTP is the technology used to transmit audio and video over IP networks. Web users weren't affected.

WhatsApp didn't immediately respond to a request for comment.