diff --git a/packages/oo7-substrate/yarn.lock b/packages/oo7-substrate/yarn.lock
index 8c3f3eb..259e710 100644
--- a/packages/oo7-substrate/yarn.lock
+++ b/packages/oo7-substrate/yarn.lock
@@ -132,9 +132,9 @@ bs58@^4.0.1:
     base-x "^3.0.2"
 
 buffer@^5.2.1:
-  version "5.2.1"
-  resolved "https://registry.yarnpkg.com/buffer/-/buffer-5.2.1.tgz#dd57fa0f109ac59c602479044dca7b8b3d0b71d6"
-  integrity sha512-c+Ko0loDaFfuPWiL02ls9Xd3GO3cPVmUobQ6t3rXNUk304u6hGq+8N/kFi+QEIKhzK3uwolVhLzszmfLmMLnqg==
+  version "5.4.2"
+  resolved "https://registry.yarnpkg.com/buffer/-/buffer-5.4.2.tgz#2012872776206182480eccb2c0fba5f672a2efef"
+  integrity sha512-iy9koArjAFCzGnx3ZvNA6Z0clIbbFgbdWQ0mKD3hO0krOrZh8UgA6qMKcZvwLJxS+D6iVR76+5/pV56yMNYTag==
   dependencies:
     base64-js "^1.0.2"
     ieee754 "^1.1.4"