diff --git a/TechnitiumLibrary.Security.Cryptography/PBKDF2.cs b/TechnitiumLibrary.Security.Cryptography/PBKDF2.cs
index b0199d5d..131e67e0 100644
--- a/TechnitiumLibrary.Security.Cryptography/PBKDF2.cs
+++ b/TechnitiumLibrary.Security.Cryptography/PBKDF2.cs
@@ -1,6 +1,7 @@
 /*
 Technitium Library
 Copyright (C) 2024  Shreyas Zare (shreyas@technitium.com)
+Copyright (C) 2026  Zafer Balkan (zafer@zaferbalkan.com)
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -55,7 +56,7 @@ public static PBKDF2 CreateHMACSHA1(string password, byte[] salt, int iterationC
 
         public static PBKDF2 CreateHMACSHA1(byte[] password, byte[] salt, int iterationCount)
         {
-            return new PBKDF2(new HMACSHA256(password), salt, iterationCount);
+            return new PBKDF2(new HMACSHA1(password), salt, iterationCount);
         }
 
         public static PBKDF2 CreateHMACSHA1(string password, int saltLength, int iterationCount)