diff --git a/library/md4.c b/library/md4.c
index a98d0a8..3f8ddff 100644
--- a/library/md4.c
+++ b/library/md4.c
@@ -34,7 +34,7 @@
 #if defined(MBEDTLS_MD4_C)
 
 #include "mbedtls/md4.h"
-#include "mbedtls/utils.h"
+#include "mbedtls/platform_util.h"
 
 #include <string.h>
 
@@ -82,7 +82,7 @@
     if( ctx == NULL )
         return;
 
-    mbedtls_zeroize( ctx, sizeof( mbedtls_md4_context ) );
+    mbedtls_platform_zeroize( ctx, sizeof( mbedtls_md4_context ) );
 }
 
 void mbedtls_md4_clone( mbedtls_md4_context *dst,