CVE-2006-1927
Cisco IOS XR, when configured for Multi Protocol Label Switching (MPLS) and running on Cisco CRS-1 or Cisco 12000 series routers, allows remote attackers to cause a denial of service (Line card crash) via certain MPLS packets, as identified by Cisco bug ID CSCsc77475.
Date published : 2006-04-20
http://www.securityfocus.com/bid/17607
http://www.cisco.com/warp/public/707/cisco-sa-20060419-xr.shtml