Hello,
yesterday I got within a minute three times the above warning in my log
file on Tor 0.2.7.6.
Could somebody please explain to me what it means and how to solve?
Someone tried to login to your control port with the wrong password.
Are you running a relay monitor? (It could be misconfigured.)
Is your ControlPort bound to a non-loopback address?
Are you running in a FreeBSD jail or OpenVZ VM?
They can bind to non-loopback addresses unexpectedly.
Are you running an exit?
Have you set your exit policy to block all local addresses on your relay?
Tor tries to find and block all local addresses, sometimes it can't discover all of them.
Is there a source where I can possibly find answers on this and other
warnings?
Unfortunately, there's no reference containing all of Tor's warnings.