diff --git a/docker/testing/distributed/sebuniversal.Dockerfile b/docker/testing/distributed/sebuniversal.Dockerfile
index 3a6e2fa3..8366caa6 100644
--- a/docker/testing/distributed/sebuniversal.Dockerfile
+++ b/docker/testing/distributed/sebuniversal.Dockerfile
@@ -18,7 +18,7 @@ COPY  seb-server.jar /sebserver/seb-server.jar
 
 WORKDIR /sebserver
 
-CMD if [ ${SEBSERVER_MODE} == "gui" ]; then exec java \
+CMD if [ "${SEBSERVER_MODE}" == "gui" ]; then exec java \
     -Xms64M \
     -Xmx1G \
     -jar "seb-server.jar" \
@@ -39,4 +39,4 @@ CMD if [ ${SEBSERVER_MODE} == "gui" ]; then exec java \
     --sebserver.password="${SECRET}" ; \
     fi;
 
-EXPOSE 8080
\ No newline at end of file
+EXPOSE 8080