diff --git a/server/src/main/java/org/opensearch/cluster/metadata/WeightedRoutingMetadata.java b/server/src/main/java/org/opensearch/cluster/metadata/WeightedRoutingMetadata.java
index bc24dd22f5c6e..0fdd025acbfb6 100644
--- a/server/src/main/java/org/opensearch/cluster/metadata/WeightedRoutingMetadata.java
+++ b/server/src/main/java/org/opensearch/cluster/metadata/WeightedRoutingMetadata.java
@@ -99,7 +99,7 @@ public static NamedDiff<Metadata.Custom> readDiffFrom(StreamInput in) throws IOE
     public static WeightedRoutingMetadata fromXContent(XContentParser parser) throws IOException {
         String attrKey = null;
         Double attrValue;
-        String attributeName = null;
+        String attributeName = "";
         Map<String, Double> weights = new HashMap<>();
         WeightedRouting weightedRouting;
         XContentParser.Token token;