diff --git a/go.mod b/go.mod
index dbffc0c..fc58d62 100644
--- a/go.mod
+++ b/go.mod
@@ -2,4 +2,4 @@ module github.com/at-wat/mqtt-go
 
 go 1.18
 
-require golang.org/x/net v0.30.0
+require golang.org/x/net v0.33.0
diff --git a/go.sum b/go.sum
index b338806..16660ab 100644
--- a/go.sum
+++ b/go.sum
@@ -1,2 +1,2 @@
-golang.org/x/net v0.30.0 h1:AcW1SDZMkb8IpzCdQUaIq2sP4sZ4zw+55h6ynffypl4=
-golang.org/x/net v0.30.0/go.mod h1:2wGyMJ5iFasEhkwi13ChkO/t1ECNC4X4eBKkVFyYFlU=
+golang.org/x/net v0.33.0 h1:74SYHlV8BIgHIFC/LrYkOGIwL19eTYXQ5wc6TBuO36I=
+golang.org/x/net v0.33.0/go.mod h1:HXLR5J+9DxmrqMwG9qjGCxZ+zKXxBru04zlTvWlWuN4=