diff --git a/internal/topology/variables/clusterclass_variable_validation.go b/internal/topology/variables/clusterclass_variable_validation.go
index f3013f191e03..0bb849c27b8f 100644
--- a/internal/topology/variables/clusterclass_variable_validation.go
+++ b/internal/topology/variables/clusterclass_variable_validation.go
@@ -149,6 +149,7 @@ func validateRootSchema(schema *clusterv1.JSONSchemaProps, fldPath *field.Path)
 	}); err != nil {
 		return append(allErrs, field.Invalid(fldPath, "", fmt.Sprintf("failed to build validator: %v", err)))
 	}
+
 	allErrs = append(allErrs, validateSchema(apiExtensionsSchema, fldPath)...)
 	return allErrs
 }
@@ -158,13 +159,11 @@ func validateSchema(schema *apiextensions.JSONSchemaProps, fldPath *field.Path)
 	// Validate that type is one of the validVariableTypes.
 	switch {
 	case len(schema.Type) == 0:
-		return field.ErrorList{field.Required(fldPath.Child("type"), "openAPIV3Schema.type cannot be empty")}
+		return field.ErrorList{field.Required(fldPath.Child("type"), "type cannot be empty")}
 	case !validVariableTypes.Has(schema.Type):
 		return field.ErrorList{field.NotSupported(fldPath.Child("type"), schema.Type, validVariableTypes.List())}
 	}
 
-	// validate enums and example here.
-
 	// If the structural schema is valid, ensure a schema validator can be constructed.
 	validator, _, err := validation.NewSchemaValidator(&apiextensions.CustomResourceValidation{
 		OpenAPIV3Schema: schema,
diff --git a/internal/topology/variables/clusterclass_variable_validation_test.go b/internal/topology/variables/clusterclass_variable_validation_test.go
index 4c42e4f7c4b0..6da1308abc62 100644
--- a/internal/topology/variables/clusterclass_variable_validation_test.go
+++ b/internal/topology/variables/clusterclass_variable_validation_test.go
@@ -495,6 +495,33 @@ func Test_ValidateClusterClassVariable(t *testing.T) {
 			},
 			wantErr: true,
 		},
+		{
+			name: "fail if variable is an object with a top level default value invalidated by the given schema",
+			clusterClassVariable: &clusterv1.ClusterClassVariable{
+				Name: "var",
+				Schema: clusterv1.VariableSchema{
+					OpenAPIV3Schema: clusterv1.JSONSchemaProps{
+						Type: "object",
+						Default: &apiextensionsv1.JSON{
+							Raw: []byte(`{"spec":{"replicas": -100}}`),
+						},
+						Properties: map[string]clusterv1.JSONSchemaProps{
+							"spec": {
+								Type: "object",
+								Properties: map[string]clusterv1.JSONSchemaProps{
+									"replicas": {
+										Type: "integer",
+										//Default: &apiextensionsv1.JSON{Raw: []byte(`-100`)},
+										Minimum: pointer.Int64(1),
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			wantErr: true,
+		},
 		{
 			name: "pass on variable with an example that is invalid by the given schema",
 			clusterClassVariable: &clusterv1.ClusterClassVariable{
diff --git a/internal/topology/variables/schema.go b/internal/topology/variables/schema.go
index 48287d6fc148..36145dad0cc0 100644
--- a/internal/topology/variables/schema.go
+++ b/internal/topology/variables/schema.go
@@ -122,7 +122,7 @@ func convertToAPIExtensionsJSONSchemaProps(schema *clusterv1.JSONSchemaProps, fl
 			apiExtensionsSchema, err := convertToAPIExtensionsJSONSchemaProps(&p, fldPath.Child("properties").Key(propertyName))
 			if err != nil {
 				allErrs = append(allErrs, field.Invalid(fldPath.Child("properties").Key(propertyName), "",
-					fmt.Sprintf("failed to convert schema of property: %v", err)))
+					fmt.Sprintf("failed to convert schema: %v", err)))
 			} else {
 				props.Properties[propertyName] = *apiExtensionsSchema
 			}
@@ -133,7 +133,7 @@ func convertToAPIExtensionsJSONSchemaProps(schema *clusterv1.JSONSchemaProps, fl
 		apiExtensionsSchema, err := convertToAPIExtensionsJSONSchemaProps(schema.Items, fldPath.Child("items"))
 		if err != nil {
 			allErrs = append(allErrs, field.Invalid(fldPath.Child("items"), "",
-				fmt.Sprintf("failed to convert schema of items: %v", err)))
+				fmt.Sprintf("failed to convert schema: %v", err)))
 		} else {
 			props.Items = &apiextensions.JSONSchemaPropsOrArray{
 				Schema: apiExtensionsSchema,