4.2.1 Spaning Tree BPDU Protect

Information

This sequence describes configuring Spanning Tree's BPDU Protect feature

Various security mechanisms are in place to protect spanning true configurations from interference and rogue devices or unwarranted changes to the network. BPDU protection secures the active topology by preventing spoofed BPDU packets from entering the network. Typically, BPDU protection is applied on edge ports connected to end user devices that do not run STP. If STP BPDU packets are received on a protected port, BPDU guard disables the port and an alert is sent.

NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.

Solution

switch(config)# interface 1/1/20
switch(config-if)# no shutdown
switch(config-if)# no routing
switch(config-if)# vlan access 10
switch(config-if)# spanning-tree bpdu-guard
switch(config-if)# exit

Impact:

While BPDU protect will prevent spoofed BPDU traffic from entering the network, there are potential impacts to the network including: When a BPDU packet is received the receiving port enters an error state and shuts down, resulting in loss of connectivity of connected devices If BPDU protect is mis-configuired and enabled on a port connected to another switch actively participating in the spanning tree, a loop can occur, leading to broadcast storms and network instability.

See Also

https://workbench.cisecurity.org/benchmarks/24202

Item Details

Category: ACCESS CONTROL, RISK ASSESSMENT, SYSTEM AND COMMUNICATIONS PROTECTION, SYSTEM AND INFORMATION INTEGRITY

References: 800-53|AC-17, 800-53|AC-17(1), 800-53|RA-5, 800-53|SC-7, 800-53|SI-4, CSCv7|12.2

Plugin: ArubaOS

Control ID: 198d3b20b37bd4a0d52ef38a4b3478f1c05742efda39579fd64aac1d93c7823b