Title

The Juniper EX switch must be configured to assign appropriate user roles or access levels to authenticated users. (Cat I impact)

Discussion

Successful identification and authentication must not automatically give an entity full access to a network device or security domain. The lack of authorization-based access control could result in the immediate compromise and unauthorized access to sensitive information. All DoD systems must be properly configured to incorporate access control methods that do not rely solely on authentication for authorized access. Authorization is the process of determining whether an entity, once authenticated, is permitted to access a specific asset or set of resources. Information systems use access control policies and enforcement mechanisms to implement this requirement. Authorization procedures and controls must be implemented to ensure each authenticated entity also has a validated and current authorization. Some network devices are pre-configured with security groups. Other network devices enable operators to create custom security groups with custom permissions. For example, an ISSM may require read-only access to audit the network device. Operators may create an audit security group, define permissions and access levels for members of the group, and then assign the ISSM’s user persona to the audit security group. This is still considered privileged access, but the ISSM’s security group is more restrictive than the network administrator’s security group. Network devices that rely on AAA brokers for authentication and authorization services may need to identify the available security groups or access levels available on the network devices and convey that information to the AAA operator. Once the AAA broker identifies the user persona on the centralized directory service, the user’s security group memberships can be retrieved. The AAA operator may need to create a mapping that links target security groups from the directory service to the appropriate security groups or access levels on the network device. Once these mappings are configured, authorizations can happen dynamically, based on each user’s directory service group membership.

Check Content

If the network device is configured to use a AAA service account, and the AAA broker is configured to assign authorization levels based on centralized user account group memberships on behalf of the network device, that will satisfy this objective. Because the responsibility for meeting this objective is transferred to the AAA broker, this requirement is not applicable for the local network device. This requirement may be verified by demonstration or configuration review. Juniper switches use role-based access controls (RBAC) to assign privilege levels. Account definitions in Junos are either "local" or "template", discriminated by the presence of an authentication stanza. Local accounts have an authentication stanza and support both external and/or local authentication depending upon the authentication order. Template accounts do not have an authentication stanza and only support external authentication. Every account (local and template) must be assigned a login class by an authorized administrator. Verify each account is assigned a login class with appropriate permissions based upon organizational requirements. Login classes support optional allow- and deny- directives as shown in the examples. Organizational requirements may require different allow- and deny- directives, or no directives at all. [edit system login] class <name> { idle-timeout 10; permissions all; deny-commands "^clear (log|security log)|^(clear|show) security alarms alarm-type idp|^request (security|system set-encryption-key|system firmware upgrade re|system decrypt)|^rollback"; deny-configuration-regexps [ "security alarms potential-violation idp" "security (ike|ipsec) (policy|proposal)" "security ipsec ^vpn$ .* manual (authentication|encryption|protocol|spi)" "security log" "system fips self-test after-key-generation" "system (archival|syslog|root-authentication|authentication-order|master-password)" "system services ssh (protocol-version|root-login)" "system login password" "system login user [a-zA-Z0-9_-]+ (authentication|class)" "system login class [a-zA-Z0-9_-]+ (permissions|deny-|allow-)" ]; } class <name-1> { idle-timeout 10; permissions [ configure maintenance security system-control trace view-configuration ]; allow-commands "^clear (log|security log)|^show cli authorization"; deny-commands "^clear (security alarms|system login lockout)|^file (copy|delete|list|rename|show)|^request (security|system set-encryption-key|system firmware upgrade re)|^rollback|^set date|^show security (alarms|dynamic-policies|match-policies|policies)|^start shell|^request system (decrypt|halt|reboot|software|zeroize)"; deny-configuration-regexps [ "system (login|internet-options|scripts|services|time-zone|^[a-r]+)" "security services event-options" ]; security-role audit-administrator; } Example local and template accounts: user <account of last resort> { uid 2000; class <name>; authentication { encrypted-password "$6$HEQnJP/W$/QD...<snip>...5r./"; ## SECRET-DATA } } user <account name> { uid 2015; class <name-1>; } Note: Accounts without an authentication stanza are template accounts, must be externally authenticated, and cannot log in locally. Verify the network device is configured to assign appropriate user roles or access levels to authenticated users. This requirement may be verified by demonstration or configuration review. If the network device does not enforce the assigned privilege level for each administrator and authorizations for access to all commands relative to the privilege level, this is a finding.

Fix Text

Configure the network device to assign appropriate user roles or access levels to authenticated users, or configure the network device to leverage an AAA solution that will satisfy this objective. set system login class <name> permissions <permission sets or 'all'> set system login class <name> deny-commands <appropriate commands to deny> set system login class <name> deny-configuration-regexps <appropriate configuration hierarchy to deny> set system login user <account name> class <name>

Additional Identifiers

Rule ID: SV-253883r879530_rule

Vulnerability ID: V-253883

Group Title: SRG-APP-000033-NDM-000212

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.