MSU Listserv


MSUNAG Archives

MSUNAG Archives


MSUNAG@LIST.MSU.EDU


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Monospaced Font

LISTSERV at MSU

LISTSERV at MSU

MSUNAG Home

MSUNAG Home

MSUNAG  September 2003

MSUNAG September 2003

Subject:

Re: open ssh bug?

From:

Joe Budzyn <[log in to unmask]>

Reply-To:

MSU Network Administrators Group <[log in to unmask]>

Date:

Tue, 16 Sep 2003 14:39:29 -0400

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (176 lines)

I have been following these reports this afternoon. I was waiting for a good
report to share, and they just arrived. I just sent the FreeBSD security
advisory to the msusec mailing list. Here is the OpenBSD advisory.

From: Chris Wysopal <[log in to unmask]>
Subject: [VulnWatch] OpenSSH Security Advisory: buffer.adv


List: openbsd-misc
Subject: OpenSSH Security Advisory: buffer.adv
From: Markus Friedl <markus () openbsd ! org>
Date: 2003-09-16 12:32:15
[Download message RAW]

This is the 1st revision of the Advisory.

This document can be found at: http://www.openssh.com/txt/buffer.adv

1. Versions affected:

        All versions of OpenSSH's sshd prior to 3.7 contain a buffer
        management error. It is uncertain whether this error is
        potentially exploitable, however, we prefer to see bugs
        fixed proactively.

2. Solution:

        Upgrade to OpenSSH 3.7 or apply the following patch.

Appendix:

Index: buffer.c
===================================================================
RCS file: /cvs/src/usr.bin/ssh/buffer.c,v
retrieving revision 1.16
retrieving revision 1.17
diff -u -r1.16 -r1.17
--- buffer.c 26 Jun 2002 08:54:18 -0000 1.16
+++ buffer.c 16 Sep 2003 03:03:47 -0000 1.17
@@ -69,6 +69,7 @@
 void *
 buffer_append_space(Buffer *buffer, u_int len)
 {
+ u_int newlen;
        void *p;

        if (len > 0x100000)
@@ -98,11 +99,13 @@
                goto restart;
        }
        /* Increase the size of the buffer and retry. */
- buffer->alloc += len + 32768;
- if (buffer->alloc > 0xa00000)
+
+ newlen = buffer->alloc + len + 32768;
+ if (newlen > 0xa00000)
                fatal("buffer_append_space: alloc %u not supported",
- buffer->alloc);
- buffer->buf = xrealloc(buffer->buf, buffer->alloc);
+ newlen);
+ buffer->buf = xrealloc(buffer->buf, newlen);
+ buffer->alloc = newlen;
        goto restart;
        /* NOTREACHED */
 }


On Tue, Sep 16, 2003 at 01:59:38PM -0400, Uwe Rossbach wrote:
> Does anyone have a confirmation of this slashdot story and Full
> Disclosure posting. The only thing I noticed is that there is a new
> openSSH version (3.7) as of 5 am today on the server in Canada. The
> exploit looks for root access by trying a large number of accounts and
> connection requests. Leading to denial of service if not successful. Uwe
> Rossbach
>
>
>
> "
>
>
> [Full-Disclosure] new ssh exploit?
>
> *christopher neitzert * [log in to unmask] <mailto:chris%40neitzert.com>
> /Mon, 15 Sep 2003 13:48:34 -0400/
>
> * Previous message: [Full-Disclosure] new ssh exploit?
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/010103.html>
> * Next message: [Full-Disclosure] new ssh exploit?
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/010120.html>
> * *Messages sorted by:* [ date ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/date.html#10116>
> [ thread ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/thread.html#10116>
> [ subject ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/subject.html#10116>
> [ author ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/author.html#10116>
>
>
> ------------------------------------------------------------------------
>
> --=-sz+BJAPCz1yL37OtGOWm
> Content-Type: text/plain
> Content-Transfer-Encoding: quoted-printable
>
> More on this;
>
> The systems in question are FreeBSD, RedHat, Gentoo, and Debian all
> running the latest versions of OpenSSH.
>
> The attack makes an enormous amount of ssh connections and attempts
> various offsets until it finds one that works permitting root login.
>
> I have received numerous messages from folks requesting anonymity or
> direct-off-list-reply confirming this exploit;
>
> The suggestions I have heard are:
>
> Turn off SSH and
>
> 1. upgrade to lsh.
>
> or
>
> 2. add explicit rules to your edge devices allowing ssh from only-known
> hosts.
>
> or
>
> 3. put ssh behind a VPN on RFC-1918 space.
>
> thanks.
>
>
>
>
> On Mon, 2003-09-15 at 12:02, christopher neitzert wrote:
> >/ Does anyone know of or have source related to a new, and unpublished ssh
> />/ exploit? An ISP I work with has filtered all SSH connections due to
> />/ several root level incidents involving ssh. Any information is
> />/ appreciated.
> />/=20
> />/=20
> /--=20
> Christopher Neitzert - GPG Key ID: 7DCC491B
>
> --=-sz+BJAPCz1yL37OtGOWm
> Content-Type: application/pgp-signature; name=signature.asc
> Content-Description: This is a digitally signed message part
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.2.2 (GNU/Linux)
>
> iD8DBQA/ZftxAXFK233MSRsRAuSUAJ9jv5aBH2wVpgv6r4sC4NaA3dnXrACglaxX
> +fZt/6hiarcw2KVtQq1i0Nk=
> =MaEF
> -----END PGP SIGNATURE-----
>
> --=-sz+BJAPCz1yL37OtGOWm--
>
>
>
> ------------------------------------------------------------------------
>
> * Previous message: [Full-Disclosure] new ssh exploit?
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/010103.html>
> * Next message: [Full-Disclosure] new ssh exploit?
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/010120.html>
> * *Messages sorted by:* [ date ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/date.html#10116>
> [ thread ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/thread.html#10116>
> [ subject ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/subject.html#10116>
> [ author ]
> <http://lists.netsys.com/pipermail/full-disclosure/2003-September/author.html#10116>

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

December 2023
June 2023
May 2022
April 2022
March 2022
February 2022
December 2021
January 2019
August 2018
June 2018
May 2018
March 2018
February 2018
January 2018
December 2017
November 2017
October 2017
September 2017
August 2017
July 2017
June 2017
May 2017
April 2017
March 2017
February 2017
January 2017
December 2016
November 2016
October 2016
September 2016
August 2016
July 2016
June 2016
May 2016
April 2016
March 2016
February 2016
January 2016
December 2015
November 2015
October 2015
September 2015
August 2015
July 2015
June 2015
May 2015
April 2015
March 2015
February 2015
January 2015
December 2014
November 2014
October 2014
September 2014
August 2014
July 2014
June 2014
May 2014
April 2014
March 2014
February 2014
January 2014
December 2013
November 2013
October 2013
September 2013
August 2013
July 2013
June 2013
May 2013
April 2013
March 2013
February 2013
January 2013
December 2012
November 2012
October 2012
September 2012
August 2012
July 2012
June 2012
May 2012
April 2012
March 2012
February 2012
January 2012
December 2011
November 2011
October 2011
September 2011
August 2011
July 2011
June 2011
May 2011
April 2011
March 2011
February 2011
January 2011
December 2010
November 2010
October 2010
September 2010
August 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
November 2009
October 2009
September 2009
August 2009
July 2009
June 2009
May 2009
April 2009
March 2009
February 2009
January 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007
May 2007
April 2007
March 2007
February 2007
January 2007
December 2006
November 2006
October 2006
September 2006
August 2006
July 2006
June 2006
May 2006
April 2006
March 2006
February 2006
January 2006
December 2005
November 2005
October 2005
September 2005
August 2005
July 2005
June 2005
May 2005
April 2005
March 2005
February 2005
January 2005
December 2004
November 2004
October 2004
September 2004
August 2004
July 2004
June 2004
May 2004
April 2004
March 2004
February 2004
January 2004
December 2003
November 2003
October 2003
September 2003
August 2003
July 2003
June 2003
May 2003
April 2003
March 2003
February 2003
January 2003
December 2002
November 2002
September 2002
August 2002
July 2002
June 2002
May 2002
April 2002
March 2002
February 2002
January 2002
December 2001
November 2001
October 2001

ATOM RSS1 RSS2



LIST.MSU.EDU

CataList Email List Search Powered by the LISTSERV Email List Manager