diff --git a/lib/workers/repository/validate.js b/lib/workers/repository/validate.js
index 0c5e157dd004064ab4c47c8b4bd6d353adccc032..5dd48e04c4c6f9f30fa80aa222f265e697ddd071 100644
--- a/lib/workers/repository/validate.js
+++ b/lib/workers/repository/validate.js
@@ -51,15 +51,17 @@ async function validatePrs(config) {
             file === 'package.json'
               ? parsed.renovate || parsed['renovate-config']
               : parsed;
-          logger.debug({ config: toValidate }, 'Validating config');
-          const { errors } = migrateAndValidate(config, toValidate);
-          if (errors && errors.length) {
-            validations = validations.concat(
-              errors.map(error => ({
-                file,
-                message: error.message,
-              }))
-            );
+          if (toValidate) {
+            logger.debug({ config: toValidate }, 'Validating config');
+            const { errors } = migrateAndValidate(config, toValidate);
+            if (errors && errors.length) {
+              validations = validations.concat(
+                errors.map(error => ({
+                  file,
+                  message: error.message,
+                }))
+              );
+            }
           }
         }
       }