diff --git a/pb/Gemfile.lock b/pb/Gemfile.lock
index d84fd06f1..2c1f6f007 100644
--- a/pb/Gemfile.lock
+++ b/pb/Gemfile.lock
@@ -13,4 +13,4 @@ RUBY VERSION
    ruby 2.4.1p111
 
 BUNDLED WITH
-   2.2.15
+   1.17.3