Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code. Updates are available.
Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code.
The vulnerability is due to improper handling of malformed Session Initiation Protocol (SIP) messages. An unauthenticated, remote attacker could exploit this vulnerability by sending a malicious request to the targeted device. Successful exploitation could allow the attacker to execute arbitrary code.
Cisco confirmed the vulnerability in a security advisory and released updated software.
Cisco has published a list of affected Cisco IOS Software releases in the security advisory. The Vendor Announcements section of this alert contains a link to the advisory.
Attackers may require special network access to exploit this vulnerability. Devices that serve SIP network traffic may be located on isolated physical or logical networks, potentially making exploitation difficult.
A successful exploit could allow the attacker to execute arbitrary code on a targeted device. The attacker may be able to execute code that could result in complete compromise.
Cisco indicates through the CVSS score that functional exploit code exists; however, the code is not known to be publicly available.
An unauthenticated, remote attacker could exploit the vulnerability to execute arbitrary code with elevated privileges, possibly to gain complete control over the device.
The vulnerability is due to improper handling of malformed SIP messages. An unauthenticated, remote attacker could exploit this vulnerability by sending a malicious SIP message to the targeted device. Devices that are configured to process SIP messages accept requests via TCP and UDP ports 5060 and TCP port 5061. The processing of a malicious message could cause an error condition that may allow the attacker to execute arbitrary code with elevated privileges.
Administrators are advised to apply the available software updates.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Administrators may consider disabling SIP listening ports on devices that are not required to process voice network traffic.
Administrators are advised to implement an intrusion prevention system (IPS) or intrusion detection system (IDS) to help detect and prevent attacks that attempt to exploit this vulnerability.
Administrators are advised to monitor critical systems.
The Cisco Applied Intelligence team has created the following companion document to guide administrators in identifying and mitigating attempts to exploit this vulnerability prior to applying updated software: cisco-amb-20100324-voice
Cisco customers with active contracts can obtain updates through the Software Center at the following link: Cisco. Cisco customers without contracts can obtain upgrades by contacting the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via e-mail at firstname.lastname@example.org.
The urgency and severity ratings of this alert are not tailored to individual users; users may value alerts differently based upon their network configurations and circumstances. THE ALERT, AND INFORMATION CONTAINED THEREIN, ARE PROVIDED ON AN "AS IS" BASIS AND DO NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE ALERT, AND INFORMATION CONTAINED THEREIN, OR MATERIALS LINKED FROM THE ALERT, IS AT YOUR OWN RISK. INFORMATION IN THIS ALERT AND ANY RELATED COMMUNICATIONS IS BASED ON OUR KNOWLEDGE AT THE TIME OF PUBLICATION AND IS SUBJECT TO CHANGE WITHOUT NOTICE. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE ALERTS AT ANY TIME.