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Home > Products and services > CSIRTUK advisories > Advisories archive > August 2005 > Cisco - Three Security Advisories

August 2005

Cisco - Three Security Advisories

ID: 00718
Ref: 662/05
Date: 23 August 2005:13:48:07
Version: 1

Title: Cisco - Three Security Advisories
Abstract: 1. Cisco Intrusion Prevention System Vulnerable to Privilege Escalation, 2. SSL Certificate Validation Vulnerability in IDS Management Software, 3. Response to BugTraq - Cisco Clean Access Agent (Perfigo) Bypass
Vendors affected: Cisco
Applications affected: Cisco


Title
=====

Cisco - Three Security Advisories:
1. Cisco Intrusion Prevention System Vulnerable to Privilege Escalation
2. SSL Certificate Validation Vulnerability in IDS Management Software
3. Response to BugTraq - Cisco Clean Access Agent (Perfigo) Bypass


Detail
======

Security advisory summaries:

1. Cisco Intrusion Prevention Systems (IPS) are a family of network
security devices that provide network based threat prevention services.
A user with OPERATOR or VIEWER access privileges may be able to exploit
a vulnerability in the command line processing (CLI) logic to gain full
administrative control of the IPS device.

2. A malicious attacker may be able to spoof a Cisco Intrusion Detection
Sensor (IDS), or Cisco Intrusion Prevention System (IPS) by exploiting
a vulnerability in the SSL certificate checking functionality in IDSMC
and Secmon.

3. This document is provided to simplify access to Cisco responses to possible
product security vulnerability issues posted in public forums for Cisco
customers. This does not imply that Cisco perceives each of these issues as an
actual product security vulnerability.


Security advisory content follows:


1.


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


=========================================================================

Cisco Security Advisory:
Cisco Intrusion Prevention System Vulnerable to Privilege Escalation

Revision 1.0

For Public Release 2005 August 22 1700 UTC (GMT)

=========================================================================


Contents
========

Summary
Affected Products
Details
Impact
Software Versions and Fixes
Obtaining Fixed Software
Workarounds
Exploitation and Public Announcements
Status of This Notice: FINAL
Distribution
Revision History
Cisco Security Procedures

+----------------------------------------------------------------------

Summary
=======

Cisco Intrusion Prevention Systems (IPS) are a family of network
security devices that provide network based threat prevention services.

A user with OPERATOR or VIEWER access privileges may be able to exploit
a vulnerability in the command line processing (CLI) logic to gain full
administrative control of the IPS device.

Cisco has made free software available to address this vulnerability.

This advisory is available at
http://www.cisco.com/warp/public/707/cisco-sa-20050824-ips.shtml

Affected Products
=================

Vulnerable Products
+------------------

Cisco Intrusion Prevention System version 5.0(1) and 5.0(2).

Products Confirmed Not Vulnerable
+--------------------------------

Any Cisco Intrusion Detection Systems (IDS) or IPS version 4.x and
earlier.

Details
=======

A user with OPERATOR or VIEWER access privileges may be able to exploit
a vulnerability in the command line processing logic to gain full
administrative control of the IPS device. OPERATOR and VIEWER accounts
are normally non-privileged accounts used for monitoring and
troubleshooting purposes.

This vulnerability is documented in the Cisco Bug Toolkit as Bug ID
CSCsb16527.

Impact
======

Successful exploitation of this vulnerability grants an attacker full
control of the IPS Device.

With full administrative access, an attacker may use the IPS device to
bypass intrusion detection logic, run arbitrary code or perform a
denial of service attack on the network and/or IPS device.

If the IPS device is used in inline mode, an attacker may cause an
interruption of network service.

Software Versions and Fixes
===========================

This issue is fixed in IPS version 5.0(3) which is available for
download at http://www.cisco.com/cgi-bin/tablebuild.pl/ips5

Obtaining Fixed Software
========================

Customers with Service Contracts
+-------------------------------

Customers with contracts should obtain upgraded software through their
regular update channels. For most customers, this means that upgrades
should be obtained through the Software Center on Cisco's worldwide
website at http://www.cisco.com.

Customers using Third-party Support Organizations
+------------------------------------------------

Customers whose Cisco products are provided or maintained through prior
or existing agreement with third-party support organizations such as
Cisco Partners, authorized resellers, or service providers should
contact that support organization for assistance with the upgrade,
which should be free of charge.

Customers without Service Contracts
+----------------------------------

Customers who purchase direct from Cisco but who do not hold a Cisco
service contract and customers who purchase through third-party vendors
but are unsuccessful at obtaining fixed software through their point of
sale should get their upgrades by contacting the Cisco Technical
Assistance Center (TAC). TAC contacts are as follows.

* +1 800 553 2447 (toll free from within North America)
* +1 408 526 7209 (toll call from anywhere in the world)
* e-mail: tac@cisco.com

Please have your product serial number available and give the URL of
this notice as evidence of your entitlement to a free upgrade. Free
upgrades for non-contract customers must be requested through the TAC.

Please do not contact either "psirt@cisco.com" or
"security-alert@cisco.com" for software upgrades.

See http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml for
additional TAC contact information, including special localized
telephone numbers and instructions and e-mail addresses for use in
various languages.

Customers may only install and expect support for the feature sets they
have purchased. By installing, downloading, accessing or otherwise
using such software upgrades, customers agree to be bound by the terms
of Cisco's software license terms found at
http://www.cisco.com/public/sw-license-agreement.html, or as otherwise
set forth at Cisco.com Downloads at
http://www.cisco.com/public/sw-center/sw-usingswc.shtml.

Workarounds
===========

As a security best practice, you should always configure your IPS
device with a list of trusted hosts or networks that you want to have
access to the IPS sensor.

For more information on setting up IPS access lists so that only
trusted hosted and networks may access the sensor, please see

http://www.cisco.com/en/US/products/sw/secursw/ps2113/products_configuration_guide_chapter09186a008045a77c.html#wp1031536

Exploitation and Public Announcements
=====================================

The Cisco PSIRT is not aware of any public announcements or malicious
use of the vulnerability described in this advisory.

This issue was discovered during internal testing.

Status of This Notice: FINAL
============================

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

A stand-alone copy or paraphrase of the text of this security advisory
that omits the distribution URL in the following section is an
uncontrolled copy, and may lack important information or contain
factual errors.

Distribution
============

This advisory will be posted on Cisco's worldwide website at
http://www.cisco.com/warp/public/707/cisco-sa-200500824-ips.shtml

In addition to worldwide web posting, a text version of this notice is
clear-signed with the Cisco PSIRT PGP key and is posted to the
following e-mail and Usenet news recipients.

* cust-security-announce@cisco.com
* first-teams@first.org (includes CERT/CC)
* bugtraq@securityfocus.com
* cisco@spot.colorado.edu
* cisco-nsp@puck.nether.net
* full-disclosure@lists.grok.org.uk
* comp.dcom.sys.cisco@newsgate.cisco.com

Future updates of this advisory, if any, will be placed on Cisco's
worldwide website, but may or may not be actively announced on mailing
lists or newsgroups. Users concerned about this problem are encouraged
to check the above URL for any updates.

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

+----------------------------------------+
| Revision | | Initial |
| 1.0 | 2005-August-22 | 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.

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

All contents are Copyright C 1992-2005 Cisco Systems, Inc. All rights
reserved. Important Notices and Privacy Statement.

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2.


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


=========================================================================

Cisco Security Advisory:
SSL Certificate Validation Vulnerability in IDS Management Software

Revision 1.0

For Public Release 2005 August 22 1700 UTC (GMT)

=========================================================================


Contents
========

Summary
Affected Products
Details
Impact
Software Versions and Fixes
Obtaining Fixed Software
Workarounds
Exploitation and Public Announcements
Status of This Notice: FINAL
Distribution
Revision History
Cisco Security Procedures

+----------------------------------------------------------------------

Summary
=======

CiscoWorks Management Center for IDS Sensors (IDSMC) is a network
security software agent that provides configuration and signature
management for Cisco Intrusion Detection and Intrusion Prevention
systems.

A separate but closely related product, Monitoring Center for Security
(Security Monitor or Secmon), provides event collection, viewing, and
reporting capability for network devices.

A malicious attacker may be able to spoof a Cisco Intrusion Detection
Sensor (IDS), or Cisco Intrusion Prevention System (IPS) by exploiting
a vulnerability in the SSL certificate checking functionality in IDSMC
and Secmon.

Cisco has made free software available to address this vulnerability.

This advisory is available at
http://www.cisco.com/warp/public/707/cisco-sa-20050824-idsmc.shtml

Affected Products
=================

Vulnerable Products
+------------------

* IDSMC version 2.0 and version 2.1.
* CiscoWorks Monitoring Center for Security (Security Monitor or
Secmon) version 1.1 through version 2.0 and version 2.1.

Products Confirmed Not Vulnerable
+--------------------------------

* IDSMC versions 1.0 thru 1.2
* CiscoWorks Monitoring Center for Security (Security Monitor or
Secmon) version 1.0

No other Cisco products are currently known to be affected by
vulnerability.

Details
=======

A malicious attacker may be able to spoof an IDS or IPS by exploiting a
vulnerability in the SSL certificate checking functionality in IDSMC
and Secmon.

SSL certificates are used to secure and authenticate IDS and IPS
sensors, thereby ensuring safe communication across your network.

This vulnerability is documented in the Cisco Bug Toolkit as Bug ID
CSCsa50100 and CSCsb57379.

Impact
======

If exploited, the attacker may be able to gather login credentials,
submit false data to IDSMC and Secmon or filter legitimate data from
IDSMC and Secmon, thus impacting the integrity of the device and the
reporting capabilities of it.

Software Versions and Fixes
===========================

This issue is addressed in Service Pack 1 for IPSMC 2.1 and Security
Monitor 2.1. This service pack is available for download at
http://www.cisco.com/cgi-bin/tablebuild.pl/mgmt-ctr-ids-app

This service pack provides monitoring of certificate information and
provides logged messages when the certificate changes for any reason
for both IDSMC and Secmon.

In addition to logging certificate changes, this service pack allows
Secmon to optionally drop the connection should the certificate change.

Revision 2.2 of IPSMC will provide the option to drop the connection
between the sensor and IPSMC should the certificate change. This
release is anticipated to be available in late 2005.

Obtaining Fixed Software
========================

Customers with Service Contracts
+-------------------------------

Customers with contracts should obtain upgraded software through their
regular update channels. For most customers, this means that upgrades
should be obtained through the Software Center on Cisco's worldwide
website at http://www.cisco.com.

Customers using Third-party Support Organizations
+------------------------------------------------

Customers whose Cisco products are provided or maintained through prior
or existing agreement with third-party support organizations such as
Cisco Partners, authorized resellers, or service providers should
contact that support organization for assistance with the upgrade,
which should be free of charge.

Customers without Service Contracts
+----------------------------------

Customers who purchase direct from Cisco but who do not hold a Cisco
service contract and customers who purchase through third-party vendors
but are unsuccessful at obtaining fixed software through their point of
sale should get their upgrades by contacting the Cisco Technical
Assistance Center (TAC). TAC contacts are as follows.

* +1 800 553 2447 (toll free from within North America)
* +1 408 526 7209 (toll call from anywhere in the world)
* e-mail: tac@cisco.com

Please have your product serial number available and give the URL of
this notice as evidence of your entitlement to a free upgrade. Free
upgrades for non-contract customers must be requested through the TAC.

Please do not contact either "psirt@cisco.com" or
"security-alert@cisco.com" for software upgrades.

See http://www.cisco.com/warp/public/687/Directory/DirTAC.shtml for
additional TAC contact information, including special localized
telephone numbers and instructions and e-mail addresses for use in
various languages.

Customers may only install and expect support for the feature sets they
have purchased. By installing, downloading, accessing or otherwise
using such software upgrades, customers agree to be bound by the terms
of Cisco's software license terms found at
http://www.cisco.com/public/sw-license-agreement.html,
or as otherwise set forth at Cisco.com Downloads at
http://www.cisco.com/public/sw-center/sw-usingswc.shtml

Workarounds
===========

As a security best practice, you should always configure your IPS
device with a list of trusted hosts or networks that you want to have
access to the IPS sensor.

For more information on setting up IPS access lists so that only
trusted hosted and networks may access the sensor, please see
http://www.cisco.com/en/US/products/sw/secursw/ps2113/products_configuration_guide_chapter09186a008045a77c.html#wp1031536

Exploitation and Public Announcements
=====================================

The Cisco PSIRT is not aware of any public announcements or malicious
use of the vulnerability described in this advisory.

Cisco would like to thank Jan Bervar at NIL Data Communications for
bringing this to our attention.

Status of This Notice: FINAL
============================

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

A stand-alone copy or paraphrase of the text of this security advisory
that omits the distribution URL in the following section is an
uncontrolled copy, and may lack important information or contain
factual errors.

Distribution
============

This advisory will be posted on Cisco's worldwide website at
http://www.cisco.com/warp/public/707/cisco-sa-20050824-idsmc.shtml

In addition to worldwide web posting, a text version of this notice is
clear-signed with the Cisco PSIRT PGP key and is posted to the
following e-mail and Usenet news recipients.

* cust-security-announce@cisco.com
* first-teams@first.org (includes CERT/CC)
* bugtraq@securityfocus.com
* cisco@spot.colorado.edu
* cisco-nsp@puck.nether.net
* full-disclosure@lists.grok.org.uk
* comp.dcom.sys.cisco@newsgate.cisco.com

Future updates of this advisory, if any, will be placed on Cisco's
worldwide website, but may or may not be actively announced on mailing
lists or newsgroups. Users concerned about this problem are encouraged
to check the above URL for any updates.

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

+----------------------------------------+
| Revision | 2005-August | Initial |
| 1.0 | 22 | 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.

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

All contents are Copyright C 1992-2005 Cisco Systems, Inc. All rights
reserved. Important Notices and Privacy Statement.

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Version: GnuPG v1.4.0 (SunOS)

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3.


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


Cisco Security Notice: Response to BugTraq - Cisco Clean Access Agent (Perfigo)
Bypass

Revision 1.0

For Public Release 2005 August 22 1600 UTC (GMT)

+------------------------------------------------------------------------------

Contents
========

Summary
Details
Status of This Notice: FINAL
Revision History
Cisco Security Procedures
Related Information

+------------------------------------------------------------------------------

Summary
=======

This document is provided to simplify access to Cisco responses to possible
product security vulnerability issues posted in public forums for Cisco
customers. This does not imply that Cisco perceives each of these issues as an
actual product security vulnerability. This notice is provided on an "as is"
basis and does not imply any kind of guarantee or warranty. Your use of the
information on the page or materials linked from this page are at your own
risk. Cisco reserves the right to change or update this page without notice at
any time.

This notice is posted at
http://www.cisco.com/warp/public/707/cisco-sn-20050822-cca.shtml .

Details
=======

The original report is located at
http://www.securityfocus.com/archive/1/408603/30/0/threaded . Cisco responded
with the following:

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


This is in response to the email posted by 'llhansen-bugtraq@adams.edu'
on August 19, 2005.

The original email is available at
http://www.securityfocus.com/archive/1/408603/30/0/threaded .

Attached: a cleartext, PGP signed version of this same email.

Hi llhansen,
While it is correct that a user can modify the 'User-Agent' string
on access to the CCA Server authentication page in order to prevent
installation of the CCA Agent, there are some things that should be
clarified:

1) Users cannot bypass authentication irrespective of the value of
the 'User-Agent' string provided. Hence, there is no danger of
invalid users (users with no credentials or invalid credentials)
getting onto the network.

2) If there is the suspicion that a malicious user might try to
masquerade as non-Windows machines, e.g. Linux, in order to bypass
CCA Agent installation, the administrator can define Network Scanning
rules on the CCA Manager and use Nessus scans to determine the real
OS in use. This will catch users that are masquerading. For this, the
CCA administrator can either obtain the appropriate plug-ins from
Tenable or www.nessus.org - as an alternative, users can write and
integrate their own plugins.

3) Furthermore, if the malicious user installs a personal firewall or
similar software, in order to make the network scan timeout, CCA
provides options to quarantine the malicious user if the network scan
times out. Hence, such users can also get quarantined, following which
administrators can determine whether the user is masquerading or not.

CCA continues to evolve and include safeguards to prevent malicious
users from trying to bypass the checks in place.

Thank you for your work on this problem. As always, working with the
Cisco PSIRT team is the best way to verify the accuracy of information
before posting it publicly.

We do greatly appreciate the opportunity to work with researchers on
security vulnerabilities, and welcome the opportunity to review and
assist with Product Security Advisories. Our ultimate goal is to ensure
that customers have accurate information on which to base upgrade and
workaround decisions and we welcome partnership with researchers
towards that goal.

Thanks,
Dario

Quidquid latine dictum sit, altum viditur

Dario Ciccarone
CCIE #10395
Product Security Incident Response Team (PSIRT)
Cisco Systems, Inc.
dciccaro@cisco.com


> -----Original Message-----
> From: llhansen-bugtraq@adams.edu [mailto:llhansen-bugtraq@adams.edu]
> Sent: Friday, August 19, 2005 12:30 PM
> To: bugtraq@securityfocus.com
> Subject: Cisco Clean Access Agent (Perfigo) bypass
>
> Description:
> Cisco Clean Access is an easily deployed software solution
> that can automatically detect, isolate, and clean infected or
> vulnerable devices that attempt to access your network. It
> identifies whether networked devices such as laptops,
> personal digital assistants, even game consoles are compliant
> with your network's security policies and repairs any
> vulnerabilities before permitting access to the network.
>
> Vendor site:
> http://www.cisco.com/en/US/products/ps6128/
>
> Affected versions:
> This works in at least 3.5.3.1 and 3.5.4.
>
> Discovery Date:
> 2005-08-12
>
> Report Date:
> 2005-08-19
>
> Severity:
> Medium
>
> Vulnerability:
> End users can bypass the "mandatory" installation of the
> Clean Access Agent by changing the User-Agent string of their
> browser. This allows them to connect to the network without
> the host-based checks being run. If configured, remote checks
> are still run.
>
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Status of This Notice: FINAL
============================

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

A stand-alone copy or paraphrase of the text of this security advisory that
omits the distribution URL in the following section is an uncontrolled copy,
and may lack important information or contain factual errors.

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

+---------------------------------------------+
| Revision | 2005-August-22 | Initial public |
| 1.0 | | 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 .

+------------------------------------------------------------------------------

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