diff --git a/libwvdrmengine/apex/device/widevine_generic.mk b/libwvdrmengine/apex/device/widevine_generic.mk
index 933a8831..e16ddb80 100644
--- a/libwvdrmengine/apex/device/widevine_generic.mk
+++ b/libwvdrmengine/apex/device/widevine_generic.mk
@@ -1,3 +1,8 @@
+ifdef TARGET_BASE_PRODUCT
 $(call inherit-product, $(TARGET_BASE_PRODUCT))
+else
+# Fallback to a valid base product to satisfy build_test
+$(call inherit-product, $(SRC_TARGET_DIR)/product/module_arm.mk)
+endif
 
 include vendor/widevine/libwvdrmengine/apex/device/device.mk