diff --git a/go.mod b/go.mod
index a650926..7dca109 100644
--- a/go.mod
+++ b/go.mod
@@ -1,13 +1,15 @@
 module github.com/cbeuw/Cloak
 
-go 1.17
+go 1.21
+
+toolchain go1.22.2
 
 require (
 	github.com/cbeuw/connutil v0.0.0-20200411215123-966bfaa51ee3
 	github.com/gorilla/mux v1.8.1
 	github.com/gorilla/websocket v1.5.1
 	github.com/juju/ratelimit v1.0.2
-	github.com/refraction-networking/utls v1.6.2
+	github.com/refraction-networking/utls v1.6.4
 	github.com/sirupsen/logrus v1.9.3
 	github.com/stretchr/testify v1.8.1
 	go.etcd.io/bbolt v1.3.8
diff --git a/go.sum b/go.sum
index 9735195..8dcc82c 100644
--- a/go.sum
+++ b/go.sum
@@ -158,6 +158,8 @@ github.com/quic-go/quic-go v0.40.1 h1:X3AGzUNFs0jVuO3esAGnTfvdgvL4fq655WaOi1snv1
 github.com/quic-go/quic-go v0.40.1/go.mod h1:PeN7kuVJ4xZbxSv/4OX6S1USOX8MJvydwpTx31vx60c=
 github.com/refraction-networking/utls v1.6.2 h1:iTeeGY0o6nMNcGyirxkD5bFIsVctP5InGZ3E0HrzS7k=
 github.com/refraction-networking/utls v1.6.2/go.mod h1:yil9+7qSl+gBwJqztoQseO6Pr3h62pQoY1lXiNR/FPs=
+github.com/refraction-networking/utls v1.6.4 h1:aeynTroaYn7y+mFtqv8D0bQ4bw0y9nJHneGxJ7lvRDM=
+github.com/refraction-networking/utls v1.6.4/go.mod h1:2VL2xfiqgFAZtJKeUTlf+PSYFs3Eu7km0gCtXJ3m8zs=
 github.com/rogpeppe/go-internal v1.9.0 h1:73kH8U+JUqXU8lRuOHeVHaa/SZPifC7BkcraZVejAe8=
 github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=