diff --git a/data/helpers.d/network b/data/helpers.d/network
index 5d20b22ac..2dff82108 100644
--- a/data/helpers.d/network
+++ b/data/helpers.d/network
@@ -17,7 +17,7 @@ ynh_find_port () {
 	ynh_handle_getopts_args "$@"
 
 	test -n "$port" || ynh_die --message="The argument of ynh_find_port must be a valid port."
-	while ss -nltu | grep -q -w :$port       # Check if the port is free
+	while ss -nltu | grep -q -w "*:$port"       # Check if the port is free
 	do
 		port=$((port+1))	# Else, pass to next port
 	done