Cisco IOS XR Software Releases 3.3.0 to 4.2.0 contain a vulnerability when handling fragmented packets that could result in a denial of service (DoS) condition of the Cisco CRS Route Processor cards listed in the “Affected Products” section of this advisory.
The vulnerability is due to improper handling of fragmented packets.
The vulnerability could cause the route processor, which processes the packets, to be unable to transmit packets to the fabric.
Customers that are running version 4.2.1 or later of Cisco IOS XR Software, or that have previously installed the Software Maintenance Upgrades (SMU) for Cisco bug ID CSCtz62593 are not affected by this vulnerability.
Cisco has released free software updates that address this vulnerability.
This advisory is available at the following link: