diff --git a/index.js b/index.js
index d41b2378..9a94ca9f 100644
--- a/index.js
+++ b/index.js
@@ -614,7 +614,7 @@ function hash(sess) {
 
   // hash
   return crypto
-    .createHash('sha1')
+    .createHash('sha256')
     .update(str, 'utf8')
     .digest('hex')
 }