diff --git a/common/bitutil/bitutil.go b/common/bitutil/bitutil.go
index cd3e72169f..a18a6d18ee 100644
--- a/common/bitutil/bitutil.go
+++ b/common/bitutil/bitutil.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Adapted from: https://golang.org/src/crypto/cipher/xor.go
+// Adapted from: https://go.dev/src/crypto/subtle/xor_generic.go
 
 // Package bitutil implements fast bitwise operations.
 package bitutil