The Cisco BGP switch must be configured to use a unique key for each autonomous system (AS) that it peers with.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-101761	CISC-RT-000480	SV-110865r1_rule		Medium

Description
If the same keys are used between eBGP neighbors, the chance of a hacker compromising any of the BGP sessions increases. It is possible that a malicious user exists in one autonomous system who would know the key used for the eBGP session. This user would then be able to hijack BGP sessions with other trusted neighbors.

STIG	Date
Cisco IOS-XE Switch RTR Security Technical Implementation Guide	2020-05-20

Details

Check Text ( C-100649r1_chk )
Review the BGP configuration to determine if it is peering with multiple autonomous systems. Interview the ISSM and switch administrator to determine if unique keys are being used. router bgp xx no synchronization bgp log-neighbor-changes neighbor x.1.1.9 remote-as yy neighbor x.1.1.9 password yyyyyyyy neighbor x.2.1.7 remote-as zz neighbor x.2.1.7 password zzzzzzzzz If unique keys are not being used, this is a finding.

Check Text ( C-100649r1_chk )

Review the BGP configuration to determine if it is peering with multiple autonomous systems. Interview the ISSM and switch administrator to determine if unique keys are being used.

router bgp xx
no synchronization
bgp log-neighbor-changes
neighbor x.1.1.9 remote-as yy
neighbor x.1.1.9 password yyyyyyyy
neighbor x.2.1.7 remote-as zz
neighbor x.2.1.7 password zzzzzzzzz

If unique keys are not being used, this is a finding.

Fix Text (F-107445r1_fix)
Configure the switch to use unique keys for each AS that it peers with as shown in the example below: SW1(config)#router bgp xx SW1(config-switch)#neighbor x.1.1.9 password yyyyyyyy SW1(config-switch)#neighbor x.2.1.7 password zzzzzzzzz