I was messing around with my wordpress site today and I accidentally copied and pasted php code into my page from the GUI editor.
Not a good idea when combined with all the security from a security plugin. So it locked me out, I couldnt go back in to fix my changes.
So I accessed my server over SSH but you could do it with FTP as well.
Then change your security plugins folder name by adding something like a 1 or something after.
This disabled the plugin and now it works. Afterwards I renamed in back to the original.
Works fine again. Not the most elegant solution but works, and I like that.