Advisory ID: cisco-sa-20100414-csd
For Public Release 2010 April 14 16:00 UTC (GMT)
Cisco Secure Desktop contains a vulnerable ActiveX control that could
allow an attacker to execute arbitrary code with the privileges of the user who
is currently logged into the affected system. Cisco has released a free
software update that addresses this vulnerability. There is a workaround that
mitigates this vulnerability.
This advisory is posted at
Cisco Secure Desktop versions prior to 3.5.841 are affected.
No other Cisco products are currently known to be affected by this
A Cisco-signed ActiveX control that is used by Cisco Secure Desktop
fails to properly verify the integrity of an executable file that is used by
the Cisco Secure Desktop installation process. If an attacker can entice a user
to visit an attacker controlled web page, the vulnerable ActiveX control could
be invoked to download an attacker-modified package. The package could contain
a malicious executable file that executes with the privileges of the affected
user. A successful exploit could result in a complete compromise of a
vulnerable system. This vulnerability is documented in Cisco Bug ID
registered customers only)
and has been assigned the Common
Vulnerabilities and Exposures (CVE) ID CVE-2010-0589.
Cisco has provided scores for the vulnerabilities in this advisory
based on the Common Vulnerability Scoring System (CVSS). The CVSS scoring in
this Security Advisory is done in accordance with CVSS version 2.0.
CVSS is a standards-based scoring method that conveys
vulnerability severity and helps determine urgency and priority of response.
Cisco has provided a base and temporal score. Customers can
then compute environmental scores to assist in determining the impact of the
vulnerability in individual networks.
Cisco has provided an FAQ to answer additional questions
regarding CVSS at:
Cisco has also provided a CVSS calculator to help compute
the environmental impact for individual networks at:
registered customers only)
Calculate the environmental score of
CVSS Base Score - 9.3
CVSS Temporal Score - 7.7
Successful exploitation of this vulnerability could result in a
complete compromise of the affected system.
When considering software upgrades, also consult
and any subsequent advisories to determine exposure and a complete upgrade
In all cases, customers should exercise caution to be
certain the devices to be upgraded contain sufficient memory and that current
hardware and software configurations will continue to be supported properly by
the new release. If the information is not clear, contact the Cisco Technical
Assistance Center (TAC) or your contracted maintenance provider for
Cisco Secure Desktop version 3.5.841 can be downloaded at the following
Note: Cisco Secure Desktop versions 3.0 and 3.1 are
only supported for operation with certain versions of Cisco IOS software and
Cisco Adaptive Security Appliance (ASA) software version 7.x. Cisco Secure
Desktop versions 3.2 through 3.5 are only supported for operation with Cisco
ASA software version 8.x. Customers running Cisco Secure Desktop versions 3.2
through 3.5 with a supported Cisco ASA software version are encouraged to
upgrade to Cisco Secure Desktop version 3.5.841.
Customers with active software licenses for Cisco Secure Desktop
versions 3.0 and 3.1 should send email to the following address for
instructions on migrating to non-vulnerable software:
Administrators can mitigate this vulnerability by using the kill bit
feature of Microsoft Windows to prevent the loading and execution of the
vulnerable ActiveX control. Administrators must use the Class identifier
(CLSID) of the vulnerable ActiveX control to disable the control. The affected
Instructions for setting the kill bit in Microsoft Windows are
available at the following link:
Note: Kill bit settings are permanent. The settings
must be removed to regain Cisco Secure Desktop functionality. After an
administrator has updated the Cisco Secure Desktop software to a fixed version
on VPN portal devices, the kill bit must be removed from Microsoft Windows
clients in order to allow the Cisco Secure Desktop software to be upgraded.
Once the kill bit is removed, clients may be vulnerable until a fixed Cisco
Secure Desktop version is installed.
Update: Cisco Secure Desktop software version 3.5.1077
replaces the old, vulnerable ActiveX CLSID with a newly issued CLSID. New
installations and upgrading from an older version of Cisco Secure Desktop will
use the new CLSID. Once the software upgrade has been installed on client
systems, administrators can safely and permanently implement the ActiveX kill
bit workaround for the old CLSID in their environment.
Additional mitigation techniques that can be deployed on Cisco devices
within the network are available in the Cisco Applied Mitigation Bulletin
companion document for this advisory:
Cisco has released software updates that address this vulnerability. Prior to deploying software, customers should consult their
maintenance provider or check the software for feature set compatibility and
known issues specific to their environment.
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
or as otherwise set forth at Cisco.com Downloads at
Do not contact firstname.lastname@example.org or email@example.com
for software upgrades.
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
Customers whose Cisco products are provided or maintained through prior
or existing agreements with third-party support organizations, such as Cisco
Partners, authorized resellers, or service providers should contact that
support organization for guidance and assistance with the appropriate course of
action in regards to this advisory.
The effectiveness of any workaround or fix is dependent on
specific customer situations, such as product mix, network topology, traffic
behavior, and organizational mission. Due to the variety of affected products
and releases, customers should consult with their service provider or support
organization to ensure any applied workaround or fix is the most appropriate
for use in the intended network before it is deployed.
Customers who purchase direct from Cisco but do not hold a Cisco
service contract, and customers who purchase through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain software patches and bug fixes 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)
Customers should have the product serial number available and be prepared to provide the URL of this notice as evidence of entitlement to a software patch or bug fix. Customers without service contracts should request a software patch or bug fix through the TAC.
for additional TAC contact information, including localized telephone numbers,
and instructions and e-mail addresses for use in various languages.
The Cisco PSIRT is not aware of any public announcements or malicious
use of the vulnerability described in this advisory.
This vulnerability was discovered and reported to Cisco by an anonymous
researcher working with TippingPoint's Zero Day Initiative. Cisco would like to
thank TippingPoint for reporting this vulnerability and collaborating on a
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A stand-alone copy or Paraphrase of the text of this document that omits the distribution URL in the following section is an uncontrolled copy, and may lack important information or contain factual errors.
This advisory is posted on Cisco's worldwide website at:
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.
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.
Initial public release.