Cisco IOS XR Software version 4.3.1 contains a vulnerability that could result in complete packet memory exhaustion. Successful exploitation could render critical services on the affected device unable to allocate packets resulting in a denial of service (DoS) condition.
Cisco has released free software updates that address this vulnerability.
Workarounds that mitigate this vulnerability are available.
This advisory is available at the following link: http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20131002-iosxr