Information
syslog-ng will create logfiles that do not already exist on the system. This setting controls what permissions will be applied to these newly created files. It is important to ensure that log files exist and have the correct permissions to ensure that sensitive syslog-ng data is archived and protected.
Solution
Edit the /etc/syslog-ng/syslog-ng.conf and set perm option to 0640 or more restrictive: options { chain_hostnames(off); flush_lines(0); perm(0640); stats_freq(3600); threaded(yes); };