diff --git a/lib/krb5/creds.c b/lib/krb5/creds.c
index ab33fc360..0b2266333 100644
--- a/lib/krb5/creds.c
+++ b/lib/krb5/creds.c
@@ -62,6 +62,7 @@ krb5_copy_creds_contents (krb5_context context,
 {
     krb5_error_code ret;
 
+    memset(c, 0, sizeof(*c));
     ret = krb5_copy_principal (context, incred->client, &c->client);
     if (ret)
 	goto fail;