Cisco IOS XR Software contains a vulnerability that could allow an unauthenticated, adjacent attacker to cause a denial of service condition. Updates are available.
A vulnerability in parsing of malformed Multiprotocol Label Switching (MPLS) packets in Cisco IOS XR Software for Cisco Network Convergence System 6000 Series Routers could allow an unauthenticated, adjacent attacker to cause a lockup and eventual reload of a network processor unit (NPU) and a line card that is processing traffic.
The vulnerability is due to insufficient logic in parsing MPLS packets. An attacker could exploit this vulnerability by sending a malformed MPLS packet to be processed by the affected device. An exploit could allow the attacker to cause a lockup and eventual reload of a network processor unit and a line card, leading to a denial of service (DoS) condition.
Cisco has confirmed the vulnerability in a security notice and released software updates.
At the time this alert was first published, Cisco IOS XR Software version 5.1 and prior were vulnerable. Later releases of Cisco IOS XR Software may also be vulnerable.
To exploit this vulnerability, an attacker must have access to the same broadcast or collision domain as the targeted device. This access requirement decreases the likelihood of a successful exploit. In addition, the targeted device must be configured to process MPLS packets, which may require the attacker to obtain additional knowledge about the device prior to an exploit attempt.
Cisco has released a security notice at the following link: CVE-2014-3379
Customers are advised to consult Cisco bug ID CSCuq10466 for a complete list of affected product versions.
An unauthenticated, adjacent attacker could exploit this vulnerability to cause a lockup and eventual reload of a network processor unit and a line card on an affected device, resulting in a DoS condition.
The vulnerability is due to improper parsing of MPLS packets by a device running an affected version of Cisco IOS XR Software.
An attacker could exploit this vulnerability by sending a malformed MPLS packet to a targeted device. Processing the malformed MPLS packet could allow the attacker to cause a lockup and eventual reload of a network processor unit and a line card on the device, leading to a DoS condition.
Administrators are advised to apply the appropriate updates.
Administrators are advised to allow only trusted users to have network access.
Administrators are advised to monitor affected systems.
Cisco customers with active contracts should contact their Cisco support team for assistance in upgrading to a software version that includes fixes for this vulnerability. Cisco customers without contracts may contact the Cisco Technical Assistance Center at 1-800-553-2447 or 1-408-526-7209 or via email at firstname.lastname@example.org for assistance.
The security vulnerability applies to the following combinations of products.
Cisco IOS XR Software
5.1 Base | for Cisco Network Convergence System 6000 Series Routers 5.0.0, 5.0.1
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