diff --git a/src/util-threshold-config.c b/src/util-threshold-config.c
index e665d1ca91..9c7e175e06 100644
--- a/src/util-threshold-config.c
+++ b/src/util-threshold-config.c
@@ -173,6 +173,7 @@ int SCThresholdConfInitContext(DetectEngineCtx *de_ctx)
 #ifndef UNITTESTS
     FILE *fd = NULL;
 #else
+    filename = "<ut>";
     FILE *fd = g_ut_threshold_fp;
     if (fd == NULL) {
 #endif