Cisco Security Advisory: Cisco Physical Access Gateway Denial of Service Vulnerability
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Cisco Security Advisory: Cisco Physical Access Gateway Denial of
Advisory ID: cisco-sa-20090624-gateway
For Public Release 2009 June 24 1600 UTC (GMT)
A denial of service (DoS) vulnerability exists in the Cisco Physical
Access Gateway. There are no workarounds available to mitigate the
vulnerability. This vulnerability has been corrected in Cisco
Physical Access Gateway software version 1.1. Cisco has released free
software updates that address this vulnerability.
This advisory is posted at:
Cisco Physical Access Gateway running software versions prior to 1.1
Products Confirmed Not Vulnerable
Cisco Physical Access Gateway running software versions 1.1 or later
are not vulnerable. No other Cisco products are currently known to be
affected by this vulnerability.
The Cisco Physical Access Gateway is the primary means for the Cisco
Physical Access Control solution to connect door hardware, such as
locks and readers, to an IP network. Certain crafted TCP port 443
packets may cause a memory leak that could lead to a denial of
service (DoS) condition in the Cisco Physical Access Gateway. A TCP
three-way handshake is needed to exploit this vulnerability.
This vulnerability is documented in Cisco Bug ID CSCsu95864 and has
been assigned Common Vulnerabilities and Exposures (CVE) ID CVE-2009-1163.
Vulnerability Scoring Details
Cisco has provided scores for the vulnerability in this advisory
based on the Common Vulnerability Scoring System (CVSS). The CVSS
scoring in this Security Advisory is done in accordance with CVSS
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
Cisco has also provided a CVSS calculator to help compute the
environmental impact for individual networks at:
CSCsu95864 - Memory leak with certain IP packets
CVSS Base Score - 7.8
Access Vector - Network
Access Complexity - Low
Authentication - None
Confidentiality Impact - None
Integrity Impact - None
Availability Impact - Complete
CVSS Temporal Score - 6.4
Exploitability - Functional
Remediation Level - Official-Fix
Report Confidence - Confirmed
Successful exploitation of the vulnerability described in this
document may result in a memory leak. The issue could be repeatedly
exploited to cause an extended DoS condition. Connected door
hardware, such as card readers, locks, and other input/output devices
will function intermittently during extended DoS exploitation. Doors
will remain open or locked depending on the gateways configuration.
Software Versions and Fixes
When considering software upgrades, also consult
http://www.cisco.com/go/psirt and any subsequent advisories to
determine exposure and a complete upgrade solution.
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 assistance.
This vulnerability has been corrected in Cisco Physical Access
Gateway software version 1.1 and can be downloaded from the following
No workarounds are available; however, mitigations that can be
deployed on Cisco devices within the network are available in the
Cisco Applied Mitigation Bulletin companion document for this
advisory, which is available at the following link:
Obtaining Fixed Software
Cisco has released free 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 Ciscos software license terms found at:
or as otherwise set forth at Cisco.com Downloads at:
Do not contact email@example.com or firstname.lastname@example.org for
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 Ciscos
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 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
Customers without Service Contracts
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 acquire 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: email@example.com
Customers should have their product serial number available and be
prepared to give the URL of this notice as evidence of entitlement to
a free upgrade. Free upgrades for non-contract customers must be
requested through the TAC.
for additional TAC contact information, including localized telephone
numbers, and instructions and e-mail addresses for use in various languages.
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 vulnerability was found during internal testing.
Status of this Notice: FINAL
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.
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
This advisory is posted on Ciscos 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 Ciscos
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 | | Initial |
| 1.0 | 2009-June-24 | 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 Ciscos worldwide website at:
This includes instructions for press inquiries regarding Cisco security notices.
All Cisco security advisories are available at:
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