The BGP implementation in Cisco IOS 15.2, IOS XE 3.5.xS before 3.5.2S, and IOS XR 4.1.0 through 4.2.2 allows remote attackers to cause a denial of service (multiple connection resets) by leveraging a peer relationship and sending a malformed attribute, aka Bug IDs CSCtt35379, CSCty58300, CSCtz63248, and CSCtz62914.
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.