Find all file with permission to run if belong to wheel or sudo group. Bit suid active
find / -perm /u+s 2>/dev/null
The denied access is not visualized with 2>/del/null
Command to show who has access to a file or folder : lsof <file/folder name>
Is possible to use the command fuser <file name>
sudo visudo manage the user permission
id user for check the groups
ulimit -a check the limit and set it for single user
to set the limit in global level user : /etc/security/limits.conf