diff --git a/lib/update-v8/majorUpdate.js b/lib/update-v8/majorUpdate.js
index 10d74826..736c4344 100644
--- a/lib/update-v8/majorUpdate.js
+++ b/lib/update-v8/majorUpdate.js
@@ -54,7 +54,7 @@ function checkoutBranch() {
           '--sort',
           'version:refname'
         );
-        const tags = res.stdout.split('\n');
+        const tags = res.stdout.split('\n').filter(tag => versionReg.test(tag));
         const lastTag = tags[tags.length - 1];
         if (lastTag) version = lastTag;
         if (version.split('.').length === 3) {