Authentication bypass mainwp-child < 3.4.5

[Slavco Mihajloski <slavco.mihajloski () gmail com>]

https://wordpress.org/plugins/mainwp-child/ remote administration plugin
for Wordpress with 300k+ active installations.

There is authentication bypass on mainwp-child < 3.4.5 and due the nature
of the Wordpress itself, it is a RCE too.


Disclosure:
https://medium.com/websec/authentication-bypass-rce-on-300k-live-websites-using-mainwp-child-3-4-5-30a69097f633

Patch:
https://github.com/mainwp/mainwp-child/commit/1b03e47300d1ee30776a63f4d526e45e1baef4e3#diff-b7c78d39c028166665d187e06e5058a7