COMMAND
Cisco
SYSTEMS AFFECTED
Cisco Catalyst 2900XL
PROBLEM
'bash' found following. It's possible to crash Cisco Catalyst
2900XL with a empty UDP packet to port 161 when SNMP is disabled.
(Other switches also?)
The crash only occurs when the switch is booted with SNMP
disabled. Seems that SNMP is listening, even if SNMP is disabled.
This has been only tested with Software Version 12.0(5.2)XU, on
WS-C2924C-XL-EN switch.
A simple empty UDP packet sender included.
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SOLUTION
Enable SNMP, or enable SNMP and then disable SNMP.