I came across this issue with su / ssh pam module, for some reason it disallowing logins with the below error. Not sure if this will affect for a particular range of UIDs .
" su: cannot open session: Cannot make/remove an entry for the specified session"
Disabled the below entry in su and sshd as a temporary fix.
"session required pam_ns.so user_map=/tmp/user_map"
Enhance Team : These pam files are updated by Enhance , any comments on how to deal with this?