Cisco Security Advisory – Cisco IOS XR Software contains a vulnerability when handling fragmented packets that may result in a denial of service condition of the Cisco CRS Route Processor cards listed under “Affected Products”. The vulnerability affects IOS XR Software versions 3.3.0 to 4.2.0. The vulnerability is a result of improper handing of fragmented packets and 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 SMU for CSCtz62593 are not affected by this vulnerability. Cisco has released free software updates that address these vulnerabilities…. Cisco Security Advisory – Cisco IOS XR Software contains a vulnerability when handling fragmented packets that may result in a denial of service condition of the Cisco CRS Route Processor cards listed under “Affected Products”. The vulnerability affects IOS XR Software versions 3.3.0 to 4.2.0. The vulnerability is a result of improper handing of fragmented packets and 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 SMU for CSCtz62593 are not affected by this vulnerability. Cisco has released free software updates that address these vulnerabilities.

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