source: http://www.securityfocus.com/bid/675/info

Cisco devices running classic IOS are reported prone to a denial of service vulnerability. The issue occurs when a vulnerable device receives and processes a UDP packet on UDP port 514 for syslog. This issue results in a crash or hang requiring a reboot.

Vulnerable IOS software may be found on the following Cisco devices:

- Cisco routers in the AGS/MGS/CGS/AGS+, IGS, RSM, 8xx, ubr9xx, 1xxx, 25xx, 26xx, 30xx, 36xx, 38xx, 40xx, 45xx, 47xx, AS52xx, AS53xx, AS58xx, 64xx, 70xx, 72xx (including the ubr72xx), 75xx, and 12xxx series.
-Recent versions of LS1010 ATM switch.
-Catalyst 2900XL LAN switch.
-Cisco DitributedDirector. 

nmap -sU -p514 <IP-of-Cisco-device>