diff --git a/go.mod b/go.mod
index b336042..31df8c5 100644
--- a/go.mod
+++ b/go.mod
@@ -5,7 +5,7 @@ go 1.20
 require (
 	github.com/google/certificate-transparency-go v1.1.7
 	github.com/google/go-cmp v0.6.0
-	golang.org/x/crypto v0.20.0
+	golang.org/x/crypto v0.21.0
 )
 
 require (
diff --git a/go.sum b/go.sum
index 6e701c6..3a46fd3 100644
--- a/go.sum
+++ b/go.sum
@@ -5,7 +5,7 @@ github.com/google/certificate-transparency-go v1.1.7 h1:IASD+NtgSTJLPdzkthwvAG1Z
 github.com/google/certificate-transparency-go v1.1.7/go.mod h1:FSSBo8fyMVgqptbfF6j5p/XNdgQftAhSmXcIxV9iphE=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
-golang.org/x/crypto v0.20.0 h1:jmAMJJZXr5KiCw05dfYK9QnqaqKLYXijU23lsEdcQqg=
-golang.org/x/crypto v0.20.0/go.mod h1:Xwo95rrVNIoSMx9wa1JroENMToLWn3RNVrTBpLHgZPQ=
+golang.org/x/crypto v0.21.0 h1:X31++rzVUdKhX5sWmSOFZxx8UW/ldWx55cbf08iNAMA=
+golang.org/x/crypto v0.21.0/go.mod h1:0BP7YvVV9gBbVKyeTG0Gyn+gZm94bibOW5BjDEYAOMs=
 k8s.io/klog/v2 v2.100.1 h1:7WCHKK6K8fNhTqfBhISHQ97KrnJNFZMcQvKp7gP/tmg=
 k8s.io/klog/v2 v2.100.1/go.mod h1:y1WjHnz7Dj687irZUWR/WLkLc5N1YHtjLdmgWjndZn0=