FYI.

Mark.

----------  Forwarded Message  ----------

Subject: Cisco Security Response: Rootkits on Cisco IOS 
Devices
Date: Friday 23 May 2008
From: Cisco Systems Product Security Incident Response Team 
<[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


Cisco Security Response: Rootkits on Cisco IOS Devices

Document ID: 107193

http://www.cisco.com/warp/public/707/cisco-sr-20080516-rootkits.shtml

Revision 2.0

Last Updated 2008 May 22 1600 UTC (GMT)

For Public Release 2008 May 16 0400 UTC (GMT)

- ---------------------------------------------------------------------

Cisco Response
==============

This is the Cisco PSIRT response to an issue that was 
disclosed by
Mr. Sebastian Muniz of Core Security Technologies at the 
EUSecWest
security conference on May 22, 2008.

No new vulnerability on the Cisco IOS software was disclosed 
during
the presentation. To the best of our knowledge, no exploit 
code has
been made publicly available, and Cisco has not received any 
customer
reports of exploitation.

Cisco has analyzed the available information and recommends 
following
industry best-practices to improve the security of all 
network
devices. Specific recommendations are available in the 
Additional
Information section of this Security Response.

Cisco PSIRT greatly appreciates the opportunity to work with
researchers on security vulnerabilities and welcomes the 
opportunity
to review and assist in product reports. We would like to 
thank Mr.
Sebastian Muniz and Core Security Technologies for working 
with us
towards the goal of keeping Cisco networks and the Internet, 
as a
whole, secure.

Additional Information
======================

The security of Cisco IOS devices consists of multiple 
factors,
including physical and logical access to the device, 
configuration of
the device, and the inherent security of the software being 
used. The
security configuration of a device, specifically in relation 
to device
security, is conveyed using documented best practices. The 
document
entitled "Cisco Guide to Harden Cisco IOS Devices" 
(available at
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml),
represents one collection of those best practices.

The integrity of the software used on Cisco IOS devices, in 
this case
Cisco IOS software, is also important to device security. 
Depending on
severity, security issues in Cisco IOS software are 
communicated to
customers using Security Advisories, Security Responses, or 
Cisco bug
release notes. Further details are documented in the Cisco 
Security
Vulnerability Policy, available at
http://www.cisco.com/en/US/products/products_security_vulnerability_policy.html.

It is possible that an attacker could insert malicious code 
into a
Cisco IOS software image and load it onto a Cisco device 
that
supports that image. This attack scenario could occur on any 
device
that uses a form of software, given a proper set of 
circumstances.
This Security Response will describe best practices that 
network
administrators can use to reduce the risk that malicious 
code is
installed on Cisco IOS devices. Additionally, this response 
will
offer some methods that administrators can use to mitigate 
the risks
of introducing malicious code into the network.

Security Best Practices
=======================

Cisco recommends that the following security best practices 
be
implemented to improve the security posture of the network. 
These
practices are particularly relevant to ensure that Cisco IOS 
devices
only use authorized and unaltered Cisco IOS software images.

Supply Chain Integrity
+---------------------

To minimize the risk associated with malicious code, it is 
important
that network administrators develop and consistently apply a 
secure
methodology for Cisco IOS software image management. This 
secure
process must be used from the time a Cisco IOS software 
image is
downloaded from cisco.com until a Cisco IOS device begins 
using it.

Although processes may vary based on the network and its 
security and
change management requirements, the following procedure 
represents an
example of best practices that may help minimize the 
possibility of
malicious code installation.

  * When downloading a Cisco IOS software image from 
www.cisco.com,
    record the MD5 hash as presented by the Cisco IOS 
Upgrade Planner
    tool.
  * Once the image has been downloaded to an administrative
    workstation, the MD5 hash of the local file should be 
verified
    against the hash presented by the Cisco IOS Upgrade 
Planner.
  * Once the Cisco IOS software image file has been verified 
as
    authentic and unaltered, copy it to write-once media or 
media
    that can be rendered as read-only after the image has 
been
    written.
  * Verify the MD5 hash of the file written to the read-only 
media to
    detect corruption during the copy process.
  * Remove the local file on the administrative workstation.
  * Relocate the read-only media to the file server that is 
used for
    Cisco IOS software image distribution to Cisco IOS 
devices.
  * Transfer the Cisco IOS software image from the file 
server to the
    Cisco IOS device using a secure protocol that provides 
both
    authentication and encryption.
  * Verify the MD5 hash of the Cisco IOS software image on 
the Cisco
    IOS device using the procedures detailed in the 'Image 
File
    Information Using IOS Upgrade Planner' section.
  * Modify the configuration of the Cisco IOS device to load 
the new
    Cisco IOS software image upon startup.
  * Reload the Cisco IOS device to place the new software 
into
    service.

Implement Change Control
+-----------------------

Change control is a mechanism through which changes being 
made to
network devices are requested, approved, implemented, and 
audited. In
the context of ensuring the authenticity of Cisco IOS 
software images
used in the network, change control is relevant because it 
helps
greatly when determining which changes have been authorized 
and which
are unauthorized. Change control is important to help ensure 
that
only authorized and unaltered Cisco IOS software is used on 
Cisco IOS
devices in the network.

Harden the Software Distribution Server
+--------------------------------------

The server that is used to distribute software to Cisco IOS 
devices
in the network is a critical component of network security. 
Several
best practices should be implemented to help ensure the 
authenticity
and integrity of software that is distributed from this 
server. These
best practices include:

  * Application of well established operating system 
hardening
    procedures that is specific to the operating system in 
use
  * Configuration of all appropriate logging and auditing
    capabilities, including logging to write-once media
  * Placement of the software distribution server on a 
secure network
    with restricted connectivity from all but the most 
trusted
    networks
  * The use of restrictive security controls to limit 
interactive
    access (as an example, SSH) to only a subset of trusted 
network
    administrators

Utilize Up-to-Date Software
+--------------------------

Cisco IOS software used in the network must be kept 
up-to-date so
that new security functionality can be leveraged and 
exposure to
known vulnerabilities disclosed through Cisco Security 
Advisories is
minimal.

Cisco is continually evolving the security of Cisco IOS 
software
images through the implementation of new security 
functionality and
the resolution of bugs. For these reasons, it is imperative 
that
network administrators maintain their networks in a manner 
that
includes using up-to-date software. Failure to do so could 
expose
vulnerabilities that may be used to gain unauthorized access 
to a
Cisco IOS device.

Leverage Authentication, Authorization, and Accounting
+-----------------------------------------------------

The comprehensive implementation of Authentication, 
Authorization,
and Accounting (AAA) is critical to ensuring the security of
interactive access to network devices. Furthermore, AAA, and
specifically authorization and accounting functions, should 
be used
to limit the actions authenticated users can perform in 
addition to
providing an audit trail of individual user actions.

For additional information on the implementation of AAA 
please see the
the section entitled "Using Authentication, Authorization 
and
Accounting" (available at
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml#usingaaa)
of the "Cisco Guide to Harden Cisco IOS Devices".

Limit Interactive Access to Devices
+----------------------------------

Once AAA has been implemented to control which users can log 
in to
particular network devices, access control should be 
implemented to
limit from which IP addresses users may perform management 
functions
on a network device. This access control includes multiple 
security
features and solutions to limit access to a device:

  * VTY access classes
  * Management Plane Protection (MPP)
  * Control Plane Policing (CoPP)
  * Control Plane Protection (CPPr)
  * Infrastructure Access Control Lists (iACL)
  * Simple Network Management Protocol (SNMP) access lists

For more information, please consult the following sections 
of the
"Cisco Guide to Harden Cisco IOS devices": "Securing 
Interactive
Management Sessions" (available at
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml#interactmanage)
and "Fortifying the Simple Network Management Protocol" 
(available at
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml#fortify).

Leverage Centralized and Comprehensive Logging
+---------------------------------------------

For network administrators to understand events taking place 
on a
network, a comprehensive logging structure using centralized 
log
collection and correlation must be implemented. 
Additionally, a
standardized logging and time configuration must be deployed 
on all
network devices to facilitate accurate logging. Furthermore, 
logging
from the AAA functions in the network should be included in 
the
centralized logging implementation.

Once comprehensive logging is in place on a network, the 
collected
data must be used to monitor network activity for events 
that may
indicate unauthorized access to a network device, or 
unauthorized
actions by legitimate users. These types of events could 
represent
the first step in undermining the security on a Cisco IOS 
device.
Because the items below may represent unauthorized access or
unauthorized actions, they should be monitored closely:

  * The transmission of Cisco IOS software images to a Cisco 
IOS
    device using the copy command or local SCP, TFTP, or FTP 
server
    functionality.
  * The attempted execution of certain high risk EXEC 
commands. The 
    copy, gdb and tclsh commands are some examples of 
commands that
    should be monitored. This list is not exhaustive.
  * Modification of the boot environment in use on the 
network
    devices. This specifically includes the boot and 
config-register
    global configuration commands.
  * Modification of the security configuration for a Cisco 
IOS
    device. This may include the removal of VTY access 
classes or the
    logging configuration or the addition of new 
administrative
    users.
  * Logging related to the insertion or removal of storage 
media,
    such as flash devices.
  * SNMP-related logging of attempts to modify the Cisco IOS 
device
    configuration or perform file management tasks.
  * The planned and unplanned reload of the Cisco IOS 
software due to
    a software crash or the use of the reload command.

For more information, see the sections entitled "Centralize 
Log
Collection and Monitoring" (available at
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml#log)
and "Logging Best Practices" (available at
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080120f48.shtml#logbest)
of the "Cisco Guide to Harden Cisco IOS Devices".

Cisco IOS Image File Verification
+--------------------------------

Network administrators can use one of several security 
features to
verify the authenticity and integrity of Cisco IOS software 
images in
use on their network devices. It is also possible to use a 
process
that does not rely on features in the Cisco IOS software 
itself.

The following sections contain information on Cisco IOS 
software
features and administrative processes that can be used to 
verify the
authenticity and integrity of a Cisco IOS software image.

Using the MD5 File Validation Feature
+------------------------------------

The MD5 File Validation feature, added in Cisco IOS Software 
Releases
12.2(4)T and 12.0(22)S, allows network administrators to 
calculate
the MD5 hash of a Cisco IOS software image file that is 
loaded on a
device. It also allows administrators to verify the 
calculated MD5
hash against that provided by the user. Once the MD5 hash 
value of
the installed Cisco IOS image is determined, it can also be 
compared
with the MD5 hash provided by Cisco to verify integrity of 
the image
file.

Note: The MD5 File Validation feature can only be used to 
check the
integrity of a Cisco IOS software image that is stored on a 
Cisco IOS
device. It cannot be used to check the integrity of an image 
running
in memory.

MD5 hash calculation and verification using the MD5 File 
Validation
feature can be accomplished using the following command:

    verify /md5 filesystem:filename [md5-hash]
    

Network administrators can use the verify /md5 privileged 
EXEC
command to verify the integrity of image files that are 
stored on the
Cisco IOS file system of a device. The following shows how 
to use the
verify /md5 command on a Cisco IOS device:

    router#verify /md5 disk0:c7301-jk9s-mz.124-10.bin
    .....<output truncated>.....Done!
    verify /md5 (disk0:c7301-jk9s-mz.124-10.bin) = 
ad9f9c902fa34b90de8365c3a5039a5b
    
    router#
    

Network administrators can also provide an MD5 hash to the 
verify
command. If provided, the verify command will compare the 
calculated
and provided MD5 hashes as illustrated in the following 
example:

    router#verify /md5 disk0:c7301-jk9s-mz.124-10.bin 
ad9f9c902fa34b90de8365c3a5039a5b
    .....<output truncated>.....Done!
    Verified (disk0:c7301-jk9s-mz.124-10.bin) = 
ad9f9c902fa34b90de8365c3a5039a5b
    
    router#
    

If the network administrator provides an MD5 hash that does 
not match
the hash calculated by the MD5 File Validation feature, an 
error
message will be displayed. This is illustrated in the 
following
example:

    router#verify /md5 disk0:c7301-jk9s-mz.124-10.bin 
0c5be63c4e339707efb7881fde7d5324
    .....<output truncated>.....Done!
    
    %Error verifying disk0:c7301-jk9s-mz.124-10.bin
    Computed signature  = ad9f9c902fa34b90de8365c3a5039a5b
    Submitted signature = 0c5be63c4e339707efb7881fde7d5324
    
    router#
    

In the preceding examples, the verify /md5 command 
calculates and
displays the MD5 hash for the entire Cisco IOS image file. 
This
approach is in contrast to the updated verify command 
present with
the "Image Verification" feature, which calculates the hash 
for the
entire Cisco IOS image as well as specific portions of the
uncompressed Cisco IOS image file.

For additional information on how to use this feature, 
please consult
the document entitled "MD5 File Validation", which is 
available at
http://www.cisco.com/en/US/docs/ios/12_4/cfg_fund/configuration/guide/h_md5v_ps6350_TSD_Products_Configuration_Guide_Chapter.html.

Using the Image Verification Feature
+-----------------------------------

The Image Verification feature, added in Cisco IOS Software 
Releases
12.3(4)T, 12.0(26)S, and 12.2(18)S, builds on the MD5 File 
Validation
functionality to more easily allow network administrators to 
verify
the integrity of an image file that is loaded on the Cisco 
IOS file
system of a device. The purpose of the Image Verification 
feature is
to ensure that corruption of the Cisco IOS software image 
file has
not occurred. The corruption detected by this feature could 
have
occurred at any time; for example, during the download from 
Cisco.com
or the installation process.

Note: The Image Verification feature does not check the 
integrity of
the image running in memory.

Cisco IOS software image file verification using this 
feature can be
accomplished using the following commands:

  * file verify auto
  * copy [/erase] [/verify | /noverify] source-url 
destination-url
  * reload [warm] [/verify | /noverify] [text | in time 
[text] | at
    time [text] | cancel]

Note: Only the file verify auto global configuration command 
and the
verify privileged EXEC command will be covered in this 
Security
Response. For information on the copy /verify and 
reload /verify
commands, please see the section entitled "Image 
Verification"
(available at
http://www.cisco.com/en/US/docs/ios/12_4/secure/configuration/guide/h_image.html
of the "Cisco IOS Security Configuration Guide" (available 
at
http://www.cisco.com/en/US/docs/ios/security/configuration/guide/12_4/sec_12_4_book.html).

Configuring the file verify auto Command
+---------------------------------------

Network administrators can use the file verify auto global
configuration command to enable verification of all images 
that are
either copied using the copy privileged EXEC command or 
loaded using
the reload privileged EXEC command. These images are 
automatically
verified for image file integrity.

The following example shows how to configure the file verify 
auto
Cisco IOS feature:

    router#configure terminal
    router(config)#file verify auto
    router(config)#exit
    router#
    

In addition to file verify auto, both the copy and the 
reload
commands have a /verify argument that enables the Image 
Verification
feature to check the integrity of the Cisco IOS image file. 
This
argument must be used each time an image is copied to or 
reloaded on
a Cisco IOS device if the global configuration command file 
verify
auto is not present.

Using the Image Verification Cisco IOS verify Command
+----------------------------------------------------

Network administrators can also use the verify privileged 
EXEC
command, originally introduced for the "MD5 File Validation" 
feature
and updated by the "Image Verification" feature, to verify 
the
integrity of image files that are stored locally on a 
device. The
following example demonstrates how to use the updated verify 
command
on a Cisco IOS device:

    router#verify disk0:c7301-jk9s-mz.124-10.bin 
    Verifying file integrity of 
disk0:c7301-jk9s-mz.124-10.bin
    .....<output truncated>.....Done!
    Embedded Hash  MD5 : 0C5BE63C4E339707EFB7881FDE7D5324
    Computed Hash  MD5 : 0C5BE63C4E339707EFB7881FDE7D5324
    CCO Hash       MD5 : AD9F9C902FA34B90DE8365C3A5039A5B
    
    Signature Verified
    
    router#
    

In the preceding output, three MD5 hash values are displayed 
by the 
verify command. Here is an explanation of what each one of 
those MD5
hash values means:

  * Embedded Hash: MD5 hash stored by Cisco in a section of 
the Cisco
    IOS image file during the image build process; used to 
verify
    section integrity for the Cisco IOS software image file. 
This MD5
    hash value is calculated for certain sections of the 
Cisco IOS
    image file.
  * Computed Hash: MD5 hash that the "Image Verification" 
feature
    calculates for certain sections of the Cisco IOS 
software image
    file when the verify command is executed. This value 
should be
    the same as the Embedded Hash to verify section 
integrity of the
    Cisco IOS image file. If this value is not equal to the 
Embedded
    Hash, the Cisco IOS image file may be corrupted or 
intentionally
    altered.
  * CCO Hash: MD5 hash for the entire Cisco IOS image file. 
This hash
    is computed by the verify command and is not stored in 
the Cisco
    IOS software image.

For additional information please see the section 
entitled "Image
Verification" (available at
http://www.cisco.com/en/US/docs/ios/12_4/secure/configuration/guide/h_image.html)
of the "Cisco IOS Security Configuration Guide" (available 
at
http://www.cisco.com/en/US/docs/ios/security/configuration/guide/12_4/sec_12_4_book.html).

Downloading an Image File From a Cisco IOS Device
+------------------------------------------------

In certain circumstances, network administrators may 
consider moving
an existing Cisco IOS software image file from a Cisco IOS 
device to
an administrative workstation. Once on the administrative
workstation, independent tools can be used to calculate the 
MD5 hash
of the file.

Two options are available for administrators to perform this 
task.
One option allows the administrator to use the Cisco IOS 
software in
use on the device to copy the stored Cisco IOS software 
image file to
an administrative workstation. If this process is being 
carried out
for security reasons, administrators are advised to use a 
secure
protocol (such as SCP) to transfer the file. However, it is
technically possible to perform this process using other 
protocols,
including RCP, TFTP, FTP, HTTP or HTTPS. This process is 
accomplished
using the copy command as illustrated in the following 
example:

    router#copy flash:c7301-jk9s-mz.124-10.bin 
scp:c7301-jk9s-mz.124-10.bin
    Address or name of remote host []? 10.1.1.1
    Destination username [cisco]? user 
    Destination filename [c7301-jk9s-mz.124-10.bin]? <enter>
    Writing c7301-jk9s-mz.124-10.bin 
    Password: <enter password>
    ! Sink: C0644 28905508 c7301-jk9s-mz.124-10.bin
    !!!!!<output truncated>!!!!!
    28905508 bytes copied in 22.280 secs (1297375 bytes/sec)
    router#
    

A second and recommended option, one that provides an 
additional
level of security, is to restart a Cisco IOS device using a
known-good version of Cisco IOS software from a trusted 
location.
Administrators can accomplish this task using the boot 
system global
configuration command as illustrated in the following 
example:

    router#configure terminal
    Enter configuration commands, one per line.  End with 
CNTL/Z.
    router(config)#boot system ftp c7301-jk9s-mz.124-10.bin 
10.1.1.1
    router(config)#end
    router#copy running-config startup-config
    Destination filename [startup-config]? <enter>
    
    Building configuration...
    [OK]
    router#reload
    

Once the network device has been restarted with a known-good 
Cisco
IOS image, a network administrator can verify the locally 
stored
image using the verify command or by copying the Cisco IOS 
software
image to a remote file server for offline verification.

Offline Image File Verification
+------------------------------

Once a file is stored on an administrative workstation, a 
network
administrator can verify the MD5 hash for that Cisco IOS 
image file
using an MD5 hashing utility. Such utilities include md5sum 
for the
Linux operating system, md5 for the BSD operating system, 
and fsum, 
MD5summer, and WinMD5 for Microsoft Windows platforms. 
Additionally,
the size of the Cisco IOS image file can be obtained using 
the ls
command on Linux and BSD operating systems and the dir 
command on
Microsoft Windows platforms.

The following example demonstrates the MD5 calculation and 
file size
display for Linux-based systems:

    $
    $ md5sum c7301-jk9s-mz.124-10.bin
    ad9f9c902fa34b90de8365c3a5039a5b 
c7301-jk9s-mz.124-10.bin
    $
    $ ls -l c7301-jk9s-mz.124-10.bin
    -r--r--r--   1 user user 28905508 May 16 15:17 
c7301-jk9s-mz.124-10.bin
    $
    

The following example illustrates this process for 
BSD-derived
systems:

    $
    $ md5 c7301-jk9s-mz.124-10.bin
    MD5 (c7301-jk9s-mz.124-10.bin) = 
ad9f9c902fa34b90de8365c3a5039a5b
    $
    $ ls -l c7301-jk9s-mz.124-10.bin
    -r--r--r--  1 user  user  28905508 May 16 21:36 
c7301-jk9s-mz.124-10.bin
    $
    

The following example shows the use of the fsum utility and 
the dir
command on a Windows system:

    C:\>fsum -md5 c7301-jk9s-mz.124-10.bin
      
    SlavaSoft Optimizing Checksum Utility - fsum 2.52.00337
    Implemented using SlavaSoft QuickHash Library 
<www.slavasoft.com>
    Copyright (C) SlavaSoft Inc. 1999-2007. All rights 
reserved.
      
    ; SlavaSoft Optimizing Checksum Utility - fsum 
2.52.00337 <www.slavasoft.com>
    ;
    ; Generated on 05/20/08 at 00:01:13
    ;
    ad9f9c902fa34b90de8365c3a5039a5b 
*c7301-jk9s-mz.124-10.bin
     
    
    C:\>
    C:\>dir c7301-jk9s-mz.124-10.bin
    Directory of C:\
     
    05/20/2008  00:10 AM         28,905,508 
c7301-jk9s-mz.124-10.bin
                   1 File(s)     28,905,508 bytes
    
                   0 Dir(s)   1,207,291,904 bytes free
    C:\>
    

Note: The use of the fsum utility is for illustrative 
purposes only
and should not be interpreted as an endorsement of the tool.

Image File Information Using Cisco IOS Upgrade Planner
======================================================

Once the MD5 hash and file size for a Cisco IOS software 
image has
been collected, network administrators can verify 
authenticity of the
image using information provided by the Cisco IOS Upgrade 
Planner
tool during the download process. The Cisco IOS Upgrade 
Planner tool
requires a valid Cisco.com account and provides details 
about each
publicly available IOS image.

Network administrators must identify their Cisco IOS 
software release
(this can be done by using information obtained from output 
provided
by the show version command) and navigate through the Cisco 
IOS
Upgrade Planner tool to locate the image in use on the Cisco 
IOS
device. Network administrators should verify that the CCO 
Hash
calculated by the Cisco IOS verify command (part of the 
Cisco IOS
"Image Verification" feature), the MD5 hash calculated by 
the verify
/md5 command (part of the "MD5 File Validation" Cisco IOS 
feature),
or the MD5 hash calculated by a third-party utility matches 
the MD5
hash that is provided by the Cisco IOS Upgrade Planner tool.

If the MD5 hash value for the whole Cisco IOS image file 
does not
match the MD5 hash provided by Cisco, network administrators 
should
download the Cisco IOS image file from the Cisco IOS Upgrade 
Planner
and use the file verification methods described in this 
document to
verify integrity of the Cisco IOS image file.

The following is an example of the information provided by 
the Cisco
IOS Upgrade Planner tool during one of the steps required 
for
downloading a Cisco IOS software image file from 
www.cisco.com:

+----------------------------------------------+
|  Details  |             Example              |
|-----------+----------------------------------|
| Release   | 12.4.10                          |
|-----------+----------------------------------|
| Size      | 28905508                         |
|-----------+----------------------------------|
| BSD       | 47318                            |
| Checksum  |                                  |
|-----------+----------------------------------|
| Router    | 0x3b61                           |
| Checksum  |                                  |
|-----------+----------------------------------|
| MD5       | ad9f9c902fa34b90de8365c3a5039a5b |
|-----------+----------------------------------|
| Date      | 17-AUG-2006                      |
| Published |                                  |
+----------------------------------------------+

For those customers whose www.cisco.com account does not 
provide
access to the Cisco IOS Upgrade Planner tool and hence 
cannot obtain
the Cisco calculated, known-good MD5 hash value for a given 
Cisco IOS
software image, or for those customers that would prefer to 
automate
the process of validating MD5 hashes using their own tools, 
Cisco is
making available a compressed file including the Cisco IOS 
software
image name and known-good MD5 hash for all 12.0-based, 
12.1-based,
12.2-based, 12.3-based and 12.4-based Cisco IOS software 
releases.

This file can be found at
http://www.cisco.com/web/tsweb/psirt/cisco-sr-20080516-rootkits.zip
and contains a second compressed file (a set of data files 
and a
document explaining the file format) and a detached PGP 
signature for
the second compressed file. The file has been signed by the 
current
Cisco PSIRT PGP key. Information on how to obtain the 
current Cisco
PSIRT PGP key can be found in the document entitled "Cisco 
Security
Vulnerability Policy", available at
http://www.cisco.com/en/US/products/products_security_vulnerability_policy.html.

We recommend customers to uncompress the file and verify the
signature for the second file before using the data files 
for any
verification purposes.

THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT 
IMPLY ANY
KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF 
THE
INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE 
DOCUMENT IS
AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR 
UPDATE THIS
DOCUMENT AT ANY TIME.

Revision History
================

+---------------------------------------+
|          |             | Updated      |
|          |             | Additional   |
| Revision |             | Information  |
| 2.0      | 2008-May-22 | section with |
|          |             | best         |
|          |             | practices    |
|          |             | content      |
|----------+-------------+--------------|
| Revision |             | Initial      |
| 1.0      | 2008-May-16 | public       |
|          |             | release      |
+---------------------------------------+

Cisco Security Procedures

Complete information on reporting security vulnerabilities 
in Cisco
products, obtaining assistance with security incidents, and
registering to receive security information from Cisco, is 
available
on Cisco's worldwide website at
http://www.cisco.com/en/US/products/products_security_vulnerability_policy.html.
 
This includes instructions for press inquiries regarding 
Cisco
security notices.  All Cisco security advisories are 
available at
http://www.cisco.com/go/psirt.

- ---------------------------------------------------------------------

Updated: May 22, 2008                             Document 
ID: 107193

- ---------------------------------------------------------------------
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.5 (Darwin)

iD8DBQFINZ8j86n/Gc8U/uARAsXUAJ9yOvx5SyIptEYBc/vJXemY6WYnEwCfWbQ4
uEpUkfP9AXnr1lcBhM0+PAQ=
=zYdw
-----END PGP SIGNATURE-----
_______________________________________________
cust-security-announce mailing list
[EMAIL PROTECTED]
To unsubscribe, send the command "unsubscribe" in the 
subject of your message to 
[EMAIL PROTECTED]

-------------------------------------------------------

Attachment: signature.asc
Description: This is a digitally signed message part.

_______________________________________________
LUG mailing list
[email protected]
http://kym.net/mailman/listinfo/lug
%LUG is generously hosted by INFOCOM http://www.infocom.co.ug/

The above comments and data are owned by whoever posted them (including 
attachments if any). The List's Host is not responsible for them in any way.
---------------------------------------

Reply via email to