diff --git a/lib/workers/package/versions.js b/lib/workers/package/versions.js
index 5aa0b343342f1d8b9733a9c3b1c5f0d35e402541..71f51809fa0fc320cac1a91906ce8029663be4e3 100644
--- a/lib/workers/package/versions.js
+++ b/lib/workers/package/versions.js
@@ -30,7 +30,7 @@ function determineUpgrades(npmDep, config) {
   // Check for a current range and pin it
   if (isRange(currentVersion)) {
     let newVersion;
-    if (lockedVersion) {
+    if (lockedVersion && semver.valid(lockedVersion)) {
       newVersion = lockedVersion;
     } else {
       // Pin ranges to their maximum satisfying version