diff --git a/lib/libc/rpc/auth_time.c b/lib/libc/rpc/auth_time.c
index 2b9a5a929e4..3128e6d4c4f 100644
--- a/lib/libc/rpc/auth_time.c
+++ b/lib/libc/rpc/auth_time.c
@@ -323,6 +323,7 @@ __rpc_get_time_offset(td, srv, thost, uaddr, netid)
 	sprintf(ipuaddr, "%d.%d.%d.%d.0.111", a1, a2, a3, a4);
 	useua = &ipuaddr[0];
 
+	bzero((char *)&sin, sizeof(sin));
 	if (uaddr_to_sockaddr(useua, &sin)) {
 		msg("unable to translate uaddr to sockaddr.");
 		if (needfree)