AUSCERT External Security Bulletin Redistribution

              ESB-2000.170 -- NetBSD Security Advisory 2000-009
                       ftpd setproctitle vulnerability
                                14 July 2000


	AusCERT Security Bulletin Summary

Product:		ftpd
Vendor:			NetBSD
Operating System:	NetBSD

Platform:		N/A

Impact:			Execute Arbitrary Code/Commands
Access Required:	Remote

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                 NetBSD Security Advisory 2000-009

Topic:		ftpd setproctitle vulnerability.
Version:	All releases before 2000/07/08
Severity:	High: Potential remote root access.


An improper use of the setproctitle() library function by ftpd may
allow a malicious remote ftp client to subvert an FTP server,
including possibly getting remote access to a system.

Technical Details

The BSD setproctitle() function, like printf(), accepts a format
string and a variable number of arguments; the format string is
interpreted to determine how to display the other arguments to the

If the format string can contain arbitrary user-supplied data, it may
be possible to trick the program into reading or writing arbitrary
memory locations, resulting in a security compromise.

A more extensive audit of the NetBSD sources for problems of this form
is under way.

Solutions and Workarounds

This problem affects all versions of NetBSD.  Patches are available
for the NetBSD-1.4 series of releases.

If you're runing NetBSD 1.4, 1.4.1, or 1.4.2, fetch the following
patch, apply it to src/libexec/ftpd/ftpd.c using the patch(1) command,
rebuild and reinstall ftpd, and kill off any existing FTP daemons (to
ensure that any improperly granted access is revoked).


If you're running a version of NetBSD-current or the NetBSD 1.5 branch
from before 2000/07/05, you should update to a newer version of
NetBSD-current.  Similarly, if you're running a version of
NetBSD-release (NetBSD 1.4 branch) from before 2000/07/08, you should
update to a newer version of NetBSD-release.

Thanks To

Jun-ichiro Hagino <itojun@netbsd.org>

Revision History

	20000708	Initial version.

More Information

Information about NetBSD and NetBSD security can be found at
http://www.NetBSD.ORG/ and http://www.NetBSD.ORG/Security/.

Copyright 2000, The NetBSD Foundation, Inc.  All Rights Reserved.

$NetBSD: NetBSD-SA2000-009.txt,v 1.1 2000/07/08 21:03:11 sommerfeld Exp $

Version: 2.6.3ia
Charset: noconv


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