diff --git a/src/shared/hfp.c b/src/shared/hfp.c
index 5bddc96..f4747b4 100644
--- a/src/shared/hfp.c
+++ b/src/shared/hfp.c
@@ -1075,7 +1075,7 @@ static void hf_call_prefix_handler(struct hfp_hf *hfp, const char *data)
 	struct hfp_context context;
 	enum hfp_result result;
 	enum hfp_error cme_err;
-	char lookup_prefix[18];
+	char lookup_prefix[18] = {};
 	uint8_t pref_len = 0;
 	const char *prefix;
 	int i;