diff --git a/lib/krb5/crypto-des3.c b/lib/krb5/crypto-des3.c
index b61948895..d50c5cebe 100644
--- a/lib/krb5/crypto-des3.c
+++ b/lib/krb5/crypto-des3.c
@@ -202,7 +202,7 @@ _krb5_DES3_random_to_key(krb5_context context,
     DES_cblock *k;
     int i, j;
 
-    memset(x, 0, sizeof(x));
+    memset(key->keyvalue.data, 0, key->keyvalue.length);
     for (i = 0; i < 3; ++i) {
 	unsigned char foo;
 	for (j = 0; j < 7; ++j) {