when using pam_yubico.so for authentication in /etc/pam.d/sudo the sudo process hangs indefinitely and cant be killed or ctrl+c. The system has to be booted to clear the state. I have reproduced this on serveral systems physical and virtual on 12.0-RELEASE as well as 12.1-RELEASE p1-4. There is no output or logs that I have found the process just blocks forever.
FWIW you can kill it by changing terminals
( CTRL+ALT+F<num> ) and login as someone in the
wheel group and perform a ps waux | grep sudo
which should provide a pid number you HUP as in
kill -HUP <pid number>
or perhaps even killall sudo might work.
A PITA, but probably better than bouncing your box. :)
While this won't fix your issue. I just thought it
might help in the interim. :)
(In reply to Chris Hutchinson from comment #1)
I tried kill -9 on it but it never dies. I did not try kill -HUP.