diff --git a/lib/cmetrics/CMakeLists.txt b/lib/cmetrics/CMakeLists.txt
index 38a86e5f44b..4d241d833d9 100644
--- a/lib/cmetrics/CMakeLists.txt
+++ b/lib/cmetrics/CMakeLists.txt
@@ -6,7 +6,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 # CMetrics Version
 set(CMT_VERSION_MAJOR  0)
 set(CMT_VERSION_MINOR  6)
-set(CMT_VERSION_PATCH  3)
+set(CMT_VERSION_PATCH  4)
 set(CMT_VERSION_STR "${CMT_VERSION_MAJOR}.${CMT_VERSION_MINOR}.${CMT_VERSION_PATCH}")
 
 # Include helpers
diff --git a/lib/cmetrics/src/cmt_decode_msgpack.c b/lib/cmetrics/src/cmt_decode_msgpack.c
index 2e1cf31be47..4ede1bdd9ed 100644
--- a/lib/cmetrics/src/cmt_decode_msgpack.c
+++ b/lib/cmetrics/src/cmt_decode_msgpack.c
@@ -977,8 +977,11 @@ static int unpack_basic_type_meta(mpack_reader_t *reader, size_t index, void *co
     result = cmt_mpack_unpack_map(reader, callbacks, context);
 
     if (CMT_DECODE_MSGPACK_SUCCESS == result) {
-        decode_context->map->label_count = cfl_list_size(&decode_context->map->label_keys);
+	if (decode_context->map == NULL || decode_context->map->parent == NULL) {
+            return CMT_DECODE_MSGPACK_INVALID_ARGUMENT_ERROR;
+	}
 
+        decode_context->map->label_count = cfl_list_size(&decode_context->map->label_keys);
         if (decode_context->map->type == CMT_HISTOGRAM) {
             histogram = (struct cmt_histogram *) decode_context->map->parent;