The Cisco IOS XE router must limit the number of concurrent SSH sessions to an organization-defined number.

From Cisco IOS XE Release 3 NDM Security Technical Implementation Guide

Associated with: CCI-000054

SV-88635r2_rule The Cisco IOS XE router must limit the number of concurrent SSH sessions to an organization-defined number.

Vulnerability 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 is helpful in limiting risks related to 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.

Check content

Review the Cisco IOS XE router configuration to see if the device limits the number of concurrent SSH sessions to an organization-defined number. The following commands should be in the configuration: line vty 0 1 exec-timeout 60 0 session-limit 2 login authentication TEST transport input ssh transport output ssh line vty 2 4 exec-timeout 60 0 session-limit 2 login authentication TEST transport input none transport output none If the number of concurrent sessions are not limited, this is a finding.

Fix text

Configure the Cisco IOS XE router to limit the number of concurrent SSH sessions to an organization-defined number. The configuration will look similar to the example below: line vty 0 1 exec-timeout 60 0 session-limit 2 login authentication TEST transport input ssh transport output ssh line vty 2 4 exec-timeout 60 0 session-limit 2 login authentication TEST transport input none transport output none

Pro Tips

Lavender hyperlinks in small type off to the right (of CSS class id, if you view the page source) point to globally unique URIs for each document and item. Copy the link location and paste anywhere you need to talk unambiguously about these things.

You can obtain data about documents and items in other formats. Simply provide an HTTP header Accept: text/turtle or Accept: application/rdf+xml.