Cisco Security Advisory
Click Icon to Copy Verbose Score
AV:N/AC:L/Au:N/C:N/I:N/A:C/E:F/RL:OF/RC:C
-
A vulnerability in Cisco TelePresence Server devices running software versions 4.1(2.29) through 4.2(4.17) could allow an unauthenticated, remote attacker to cause the device to reload.
The vulnerability exists due to a failure of the HTTP parsing engine to handle specially crafted URLs. An attacker could exploit this vulnerability by sending multiple URL requests to an affected device. The requests will eventually time out because negotiation from the client does not occur; however, each request consumes additional memory, resulting in memory exhaustion that causes the device to crash. If successful, the attacker could utilize all available memory resources, causing the device to reload.
Cisco has released software updates that address this vulnerability. Workarounds that address this vulnerability are not available.
This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160406-cts1
-
Vulnerable Products
The following Cisco TelePresence Server devices running Cisco TelePresence Server software versions 4.1(2.29) through 4.2(4.17) are vulnerable:
- Cisco TelePresence Server 7010
- Cisco TelePresence Server Mobility Services Engine (MSE) 8710
- Cisco TelePresence Server on Multiparty Media 310
- Cisco TelePresence Server on Multiparty Media 320
- Cisco TelePresence Server on Multiparty Media 820
- Cisco TelePresence Server on Virtual Machine (VM)
Products Confirmed Not Vulnerable
No other Cisco products are currently known to be affected by this vulnerability.
-
In most instances, the log files may be used to determine if a device has been compromised. If an attacker uses inaccessible URLs to exhaust memory, the following log messages will appear:
HTTP: Info: new incoming connection “____” from <IP>:<Port>
HTTP: Info: new incoming tx tunnel channel for “____”
HTTP: Warning: failing incomplete connection “____” from <IP>:<Port>
-
There are no workarounds that address this vulnerability.
-
Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license: http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
Additionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.
When considering software upgrades, customers are advised to consult the Cisco Security Advisories and Responses archive at http://www.cisco.com/go/psirt and review subsequent advisories to determine exposure and a complete upgrade solution.
In all cases, customers should ensure that the devices to upgrade contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.
Customers Without Service Contracts
Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco Technical Assistance Center (TAC): http://www.cisco.com/en/US/support/tsd_cisco_worldwide_contacts.html
Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.
Fixed Releases
Customers should upgrade to an appropriate release as indicated in the applicable table in this section. To help ensure a complete upgrade solution, consider that this advisory is part of a collection that includes the following advisories:
- cisco-sa-20160406-cts: Cisco TelePresence Server Crafted IPv6 Packet Handling Denial of Service Vulnerability
- cisco-sa-20160406-cts1: Cisco TelePresence Server Crafted URL Handling Denial of Service Vulnerability
- cisco-sa-20160406-cts2: Cisco TelePresence Server Malformed STUN Packet Processing Denial of Service Vulnerability
In the following table, the left column lists major releases of Cisco software. The center column indicates whether a major release is affected by the vulnerability described in this advisory and the first minor release that includes the fix for this vulnerability. The right column indicates whether a major release is affected by all the vulnerabilities described in this collection of advisories and which release includes fixes for those vulnerabilities.
Cisco TelePresence Server Product First Fixed Release for This Vulnerability First Fixed Release for This Vulnerability and All Vulnerabilities Described in the Collection of Advisories Cisco TelePresence Server Crafted IPv6 Packet Handling Denial of Service Vulnerability 8710 4.2(4.23) 4.2(4.23) Cisco TelePresence Server Crafted URL Handling Denial of Service Vulnerability 7010/8710/310/320/VM 4.2(4.18) 4.2(4.23) 820 4.2(3.72) 4.2(3.72) Cisco TelePresence Server Malformed STUN Packet Denial of Service Vulnerability 7010/8710/310/320/VM 4.2(4.18) 4.2(4.23)
-
The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
-
This vulnerability was found during internal testing.
-
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
-
Show LessVersion Description Section Status Date 1.0 Initial public release. — Final 2016-April-06
-
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 standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products.