diff --git a/Makefile b/Makefile
index 4037f69ba5dab75d6d17fee19ab7d89d707be357..2acc917d4f31294c3574a01b2d2d881bf85a28d2 100644
--- a/Makefile
+++ b/Makefile
@@ -221,6 +221,7 @@ check_login_var:
 	$(call check_defined, LOGIN)
 
 check_nexus_exam_vars:
+	$(call check_defined, CERT)
 	$(call check_defined, EXAM_USER)
 	$(call check_defined, EXAM_PWD)
 
diff --git a/live_exam_os/nexus_exam_builder/Dockerfile b/live_exam_os/nexus_exam_builder/Dockerfile
index 588c061fb0e10840100fa15e716d22679609cba9..cfb4ab5a2d52c858b781a1e87792ba55938eaf36 100644
--- a/live_exam_os/nexus_exam_builder/Dockerfile
+++ b/live_exam_os/nexus_exam_builder/Dockerfile
@@ -8,5 +8,5 @@ RUN apt-get update && apt-get install -y golang-go make ca-certificates libglfw3
 RUN echo $server > /server
 RUN echo $exam_user > /exam_user
 RUN echo $exam_pwd > /exam_pwd
-RUN make build_nexus-exam SERVER=$server CERT=/nexus EXAM_USER=$exam_user EXAM_PWD=$exam_pwd
+RUN make build_nexus-exam SERVER=$server CERT=/nexus/ca-cert.pem EXAM_USER=$exam_user EXAM_PWD=$exam_pwd
 RUN ["sh"]