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From:	 Progeny Security Team 
To:	 BUGTRAQ@SECURITYFOCUS.COM
Subject: PROGENY-SA-2001-04: OpenSSH subject to traffic analysis
Date:	 Thu, 12 Apr 2001 14:03:53 -0500

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 PROGENY LINUX SYSTEMS -- SECURITY ADVISORY               PROGENY-SA-2001-04
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    Topic:          OpenSSH subject to traffic analysis

    Category:       net
    Module:         openssh
    Announced:      2001-04-12
    Credits:        Solar Designer <solar@openwall.com>
                    BugTraq Mailing List <bugtraq@securityfocus.com>
    Affects:        Progeny Debian (openssh prior to 2.5.2p2-0progeny1)
                    Debian GNU/Linux (openssh prior to 2.5.2)
    Vendor-Status:  New Version Released (openssh_2.5.2p2-0progeny1)
    Corrected:      2001-04-12
    Progeny Only:   NO

    $Id: PROGENY-SA-2001-04,v 1.8 2001/04/12 18:02:02 jdaily Exp $

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SYNOPSIS

A number of security problems existed in previous versions of OpenSSH
which would allow an attacker obtain sensitive information by passively
monitoring the encrypted SSH (Secure Shell) sessions.


PROBLEM DESCRIPTION

Solar Designer has conducted a very thorough analysis of several
weaknesses in implementations of the SSH protocol.  These weaknesses
allow for an attacker to significantly speed up brute force attacks on
passwords.  Solar Designer's complete analysis can be found at the
following page:

  http://www.openwall.com/advisories/OW-003-ssh-traffic-analysis.txt

In February of 2001, Core SDI released a security announcement which
described ways in which would allow an attacker to compromise the
session of an SSH protocol 1.5 session.  The detailed report is at the
following URL:

  http://www.core-sdi.com/advisories/ssh1_sessionkey_recovery.htm


IMPACT

Shortcomings in the OpenSSH implementation of the SSH protocol allow
malicious third parties to compromise sensitive data.


SOLUTION

Upgrade to a fixed version of OpenSSH.  You may use Progeny's OpenSSH
package, version openssh_2.5.2p2-0progeny1, for convenience.


WORKAROUND

There is no known satisfactory work around at this time.


UPDATING VIA APT-GET

 1. Ensure that your /etc/apt/sources.list file has a URI for Progeny's
    security update repository:

        deb http://archive.progeny.com/progeny updates/newton/

 2. Update your cache of available packages for apt(8).

    Example:

        # apt-get update

 3. Using apt(8), install the new ssh package.  apt(8) will download
    the update, verify it's integrity with md5, and then install the
    package on your system with dpkg(8).

    Example:

        # apt-get install ssh


UPDATING VIA DPKG

 1. Using your preferred FTP/HTTP client to retrieve the following
    updated files from Progeny's update archive at:

    http://archive.progeny.com/pub/progeny/updates/newton/

    Filename                             MD5 Checksum
    ------------------------------------ --------------------------------
    ssh_2.5.2p2-0progeny1_i386.deb       c64fdf411514850f3854a6395c5e178c

    Example:

        # wget
http://archive.progeny.com/progeny/updates/newton/ssh_2.5.2p2-0progeny1_i386.deb

 2. Use the md5sum command on the retrieved file to verify that it matches
    the md5sum provided in this advisory:

    Example:

        # md5sum ssh_2.5.2p2-0progeny1_i386.deb

 3. Then install the replacement package(s) using the dpkg command.

    Example:

        # dpkg --install ssh_2.5.2p2-0progeny1_i386.deb


MORE INFORMATION

There is no more information available at this time.

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pub  1024D/F92D4D1F 2001-04-04 Progeny Security Team <security@progeny.com>

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