diff --git a/automation/check-patch.e2e-kubevirt-ipam-controller-functests.sh b/automation/check-patch.e2e-kubevirt-ipam-controller-functests.sh
index b6b20b8e9..051d8f909 100755
--- a/automation/check-patch.e2e-kubevirt-ipam-controller-functests.sh
+++ b/automation/check-patch.e2e-kubevirt-ipam-controller-functests.sh
@@ -20,7 +20,7 @@ teardown() {
 }
 
 increase_ulimit() {
-    if [ -z "${OCI_BIN}" ];then
+    if [ -z "${OCI_BIN:-}" ];then
       export OCI_BIN=$(if podman ps >/dev/null 2>&1; then echo podman; elif docker ps >/dev/null 2>&1; then echo docker; else echo "Neither podman nor docker is available." >&2; exit 1; fi)
     fi