diff --git a/plugins/filter_kubernetes/kubernetes.c b/plugins/filter_kubernetes/kubernetes.c
index 24548e5fa68..b1c21ce9ece 100644
--- a/plugins/filter_kubernetes/kubernetes.c
+++ b/plugins/filter_kubernetes/kubernetes.c
@@ -130,7 +130,7 @@ static int merge_log_handler(msgpack_object o,
 {
     int ret;
     int new_size;
-    int root_type;
+    int root_type = FLB_PACK_JSON_UNDEFINED;
     int records = 0;
     char *tmp;
 
diff --git a/src/flb_pack.c b/src/flb_pack.c
index 28594b4f8d6..08e75137831 100644
--- a/src/flb_pack.c
+++ b/src/flb_pack.c
@@ -399,7 +399,7 @@ static int pack_json_to_msgpack_yyjson(const char *js, size_t len, char **buffer
     msgpack_packer pck;
     char *start, *end, *insitu_buf;
 
-    if (!js || !buffer || !size) {
+    if (!js || !buffer || !size || len == 0) {
         return -1;
     }