Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service condition on a targeted system. Updates are available.
Description
Cisco IOS Software contains a vulnerability that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on a targeted system.
The vulnerability is due to the improper processing of IP packets by the affected software while performing NAT. An unauthenticated, remote attacker could exploit this vulnerability by sending crafted IP packets to a targeted device that is configured for NAT. A successful exploit could allow the attacker to cause the device to become unresponsive or reload, resulting in a DoS condition.
Cisco confirmed this vulnerability and software updates are available.
Warning Indicators
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.
IntelliShield Analysis
An attacker must be able to send malicious packets to the targeted device to exploit the vulnerability. In addition, the attacker may require access to trusted, internal networks, decreasing the likelihood of a successful attack.
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 this vulnerability to cause a targeted device to reload, resulting in a DoS condition. Repeated exploitation could result in a sustained DoS condition.
Technical Information
The vulnerability is due to the improper processing of IP packets by the affected software while performing NAT.
An unauthenticated, remote attacker could exploit this vulnerability by sending crafted IP packets to a targeted device. Successful exploitation could allow the attacker to cause the vulnerable system to become unresponsive or reload, resulting in a DoS condition.
Safeguards
Administrators are advised to apply the appropriate software updates.
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.
Patches/Software
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 tac@cisco.com.
Signatures
Cisco Systems Cisco Intrusion Prevention System (IPS) 6.0
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LEGAL DISCLAIMER 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.
