diff --git a/debian/rules b/debian/rules
index 2ac25b9..2280fa4 100755
--- a/debian/rules
+++ b/debian/rules
@@ -12,6 +12,8 @@ override_dh_install:
 	dh_install
 	# original installation has duplicate docs for knock and knockd
 	rm -rf debian/knockd/usr/share/doc/knock
+	# be more restrictive
+	chmod 0600 debian/knockd/etc/knockd.conf
 
 # the standard config is unsafe
 override_dh_installsystemd: