diff --git a/ChangeLog b/ChangeLog
index 6a4b551b9..f37b7e5fd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,10 @@
      bz#2107 - cache OIDs of supported GSSAPI mechanisms before privsep
      sandboxing, as running this code in the sandbox can cause violations;
      ok markus@
+   - djm@cvs.openbsd.org 2014/02/26 20:29:29
+     [channels.c]
+     don't assume that the socks4 username is \0 terminated;
+     spotted by Ben Hawkes; ok markus@
 
 20140224
  - OpenBSD CVS Sync
diff --git a/channels.c b/channels.c
index 1052b80ca..9efe89c9c 100644
--- a/channels.c
+++ b/channels.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: channels.c,v 1.330 2014/02/15 23:05:36 djm Exp $ */
+/* $OpenBSD: channels.c,v 1.331 2014/02/26 20:29:29 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -1072,6 +1072,9 @@ channel_decode_socks4(Channel *c, fd_set *readset, fd_set *writeset)
 	buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
 	have = buffer_len(&c->input);
 	p = buffer_ptr(&c->input);
+	if (memchr(p, '\0', have) == NULL)
+		fatal("channel %d: decode socks4: user not nul terminated",
+		    c->self);
 	len = strlen(p);
 	debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
 	len++;					/* trailing '\0' */