diff --git a/config/config.schema.json b/config/config.schema.json
index ca8a4a3ec..80c303aad 100644
--- a/config/config.schema.json
+++ b/config/config.schema.json
@@ -675,7 +675,7 @@
               },
               "versions": {
                 "description": "The current istio version in the AKS cluster",
-                "type": "array"
+                "type": "string"
               },
               "targetVersion": {
                 "description": "The target istio version that will be updated to",