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Cisco Bug: CSCuw56900 - Cisco GSR 12000 UDP Port Range BFD Denial of Service (DoS) Vulnerability

Last Modified

Jan 11, 2017

Products (1)

  • Cisco 12000 Series Routers

Known Affected Releases


Description (partial)

A vulnerability in Application-Specific Integrated Circuit (ASIC) User Datagram Protocol (UDP) 
ingress receive function of the Cisco Gigabit Switch Router (GSR) 12000 Series Routers could 
allow an unauthenticated, remote attacker to cause a partial denial of service (DoS) condition 
due to one line card in the router unexpectedly restarting.

The vulnerability is due to improper input validation for the presence of a Bidirectional Forwarding 
Detection (BFD) header on the UDP packet. An attacker could exploit this vulnerability by sending a 
crafted UDP packet with a specific UDP port range and Time To Live (TTL) field to the affected device. 
An exploit could allow the attacker to cause a partial denial of service (DoS) condition due to a line 
card unexpectedly restarting.

Only line cards with serial interfaces are affected by this vulnerability.
The issue is seen in 4.3 onwards releases of IOS XR for GSR12k.
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Bug Details Include

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