The Juniper EX switch must be configured to limit privileges to change the software resident within software libraries.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-253899	JUEX-NM-000220	SV-253899r843730_rule		Medium

Description
Changes to any software components of the network device can have significant effects on the overall security of the network. Therefore, only qualified and authorized individuals should be allowed administrative access to the network device for implementing any changes or upgrades. If the network device were to enable nonauthorized users to make changes to software libraries, those changes could be implemented without undergoing testing, validation, and approval.

Description

Changes to any software components of the network device can have significant effects on the overall security of the network. Therefore, only qualified and authorized individuals should be allowed administrative access to the network device for implementing any changes or upgrades. If the network device were to enable nonauthorized users to make changes to software libraries, those changes could be implemented without undergoing testing, validation, and approval.

STIG	Date
Juniper EX Series Switches Network Device Management Security Technical Implementation Guide	2022-08-31

Details

Check Text ( C-57351r843728_chk )
Determine if the network device limits privileges to change the software resident within software libraries. 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 local authentication. 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. Installation of firmware requires the maintenance permission bit. However, even with that bit set, software installation can be limited by the "deny-commands" statement (e.g., deny-commands "^request system software"). The command takes a regular expression (REGEX) enclosed in double quotes ("). 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 { 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 { 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 { uid 2000; class ; authentication { encrypted-password "$6$HEQnJP/W$/QD......5r./"; ## SECRET-DATA } } user { uid 2015; class ; } Note: Accounts without an authentication stanza are template accounts, must be externally authenticated, and cannot log in locally. If it does not limit privileges to change the software resident within software libraries, this is a finding.

Check Text ( C-57351r843728_chk )

Determine if the network device limits privileges to change the software resident within software libraries.

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 local authentication. 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.

Installation of firmware requires the maintenance permission bit. However, even with that bit set, software installation can be limited by the "deny-commands" statement (e.g., deny-commands "^request system software"). The command takes a regular expression (REGEX) enclosed in double quotes (").

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 {
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 {
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 {
uid 2000;
class ;
authentication {
encrypted-password "$6$HEQnJP/W$/QD......5r./"; ## SECRET-DATA
}
}
user {
uid 2015;
class ;
}
Note: Accounts without an authentication stanza are template accounts, must be externally authenticated, and cannot log in locally.

If it does not limit privileges to change the software resident within software libraries, this is a finding.

Fix Text (F-57302r843729_fix)
Configure the network device to limit privileges to change the software resident within software libraries. set system login class permissions set system login class deny-commands set system login class deny-configuration-regexps set system login user class