diff --git a/monkey/monkey_island/linux/install_mongo.sh b/monkey/monkey_island/linux/install_mongo.sh
index a00a2078b..2395454b6 100644
--- a/monkey/monkey_island/linux/install_mongo.sh
+++ b/monkey/monkey_island/linux/install_mongo.sh
@@ -3,19 +3,19 @@
 export os_version_monkey=$(cat /etc/issue)
 MONGODB_DIR=$1 # If using deb, this should be: /var/monkey/monkey_island/bin/mongodb
 
-if [[ $os_version_monkey == "Ubuntu 16.04"* ]] ;
+if [[ ${os_version_monkey} == "Ubuntu 16.04"* ]] ;
 then
 	echo Detected Ubuntu 16.04
 	export tgz_url="https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1604-3.6.12.tgz"
-elif [[ $os_version_monkey == "Ubuntu 18.04"* ]] ;
+elif [[ ${os_version_monkey} == "Ubuntu 18.04"* ]] ;
 then
 	echo Detected Ubuntu 18.04
 	export tgz_url="https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-ubuntu1804-4.0.8.tgz"
-elif [[ $os_version_monkey == "Debian GNU/Linux 8"* ]] ;
+elif [[ ${os_version_monkey} == "Debian GNU/Linux 8"* ]] ;
 then
 	echo Detected Debian 8
 	export tgz_url="https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian81-3.6.12.tgz"
-elif [[ $os_version_monkey == "Debian GNU/Linux 9"* ]] ;
+elif [[ ${os_version_monkey} == "Debian GNU/Linux 9"* ]] ;
 then
 	echo Detected Debian 9
 	export tgz_url="https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian92-3.6.12.tgz"
@@ -25,15 +25,15 @@ else
 fi
 
 TEMP_MONGO=$(mktemp -d)
-pushd $TEMP_MONGO
-wget $tgz_url -O mongodb.tgz
+pushd ${TEMP_MONGO}
+wget ${tgz_url} -O mongodb.tgz
 tar -xf mongodb.tgz
 popd
 
-mkdir -p $MONGODB_DIR/bin
-cp $TEMP_MONGO/mongodb-*/bin/mongod $MONGODB_DIR/bin/mongod
-cp $TEMP_MONGO/mongodb-*/LICENSE-Community.txt $MONGODB_DIR/
-chmod a+x $MONGODB_DIR/bin/mongod
-rm -r $TEMP_MONGO
+mkdir -p ${MONGODB_DIR}/bin
+cp ${TEMP_MONGO}/mongodb-*/bin/mongod ${MONGODB_DIR}/bin/mongod
+cp ${TEMP_MONGO}/mongodb-*/LICENSE-Community.txt ${MONGODB_DIR}/
+chmod a+x ${MONGODB_DIR}/bin/mongod
+rm -r ${TEMP_MONGO}
 
 exit 0
\ No newline at end of file