CISC-ND-000010 The Cisco router must be configured to limit the number of concurrent management sessions to an organization-defined number.
All changes in this version
Maps to AC-10 via CCI-000054
Title
The Cisco router must be configured to limit the number of concurrent management sessions to an organization-defined number.
Control
Note: This requirement is not applicable to file transfer actions such as FTP, SCP, and SFTP. Review the router configuration to determine if concurrent management sessions are limited as shown in the example below: ip http secure-server ip http max-connections 2 … … … For platforms that support the session-limit command: line vty 0 4 session-limit 2 transport input ssh For those platforms that do not support the session-limit command, the sessions can also be limited by reducing the number of active vty lines as shown in the example below. line vty 0 1 transport input ssh line vty 2 4 transport input none If the router is not configured to limit the number of concurrent management sessions, this is a finding.
Discussion
Device management includes the ability to control the number of administrators and management sessions that manage a device. Limiting the number of allowed administrators and sessions per administrator based on account type, role, or access type is helpful in limiting risks related to denial-of-service (DoS) attacks. This requirement addresses concurrent sessions for administrative accounts and does not address concurrent sessions by a single administrator via multiple administrative accounts. The maximum number of concurrent sessions should be defined based upon mission needs and the operational environment for each system. At a minimum, limits must be set for SSH, HTTPS, account of last resort, and root account sessions.
Related controls
CCI-000054
Fix
Configure the router to limit the number of concurrent management sessions to an organization-defined number as shown in the example below. R4(config)#ip http max-connections 2 R4(config)#line vty 0 1 R4(config-line)#transport input ssh R4(config-line)#exit R4(config)#line vty 2 4 R4(config-line)# transport input none R4(config-line)#end To configure session limiting, use the example below. R4(config)#line vty 0 4 R4(config-line)#session-limit 2 R4(config-line)#transport input ssh