While many dont use the Facebook Messenger voice message feature, it is still very popular.
How does a Hacker listen to your Facebook voice message?
The Facebook Messenger voice chat flaw is so simple that a hacker with minimum technical skill can exploit it.
Baset explains that the issue lies in the way the chat is exchanged over HTTPS to HTTP servers.
Facebook is yet to implement a highly secure transport protocol called HSTS.
In this case, Facebook is yet to roll out HSTS policy for its chat servers.
Baset has informed Facebook security engineers about the vulnerability long back.
source: www.techworm.net