The Juniper router must be configured to protect audit information from unauthorized deletion.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-91121	JUNI-ND-000390	SV-101221r1_rule		Medium

Description
Audit information includes all information (e.g., audit records, audit settings, and audit reports) needed to successfully audit information system activity. If audit data were to become compromised, then forensic analysis and discovery of the true source of potentially malicious system activity is impossible to achieve. To ensure the veracity of audit data, the network device must protect audit information from unauthorized deletion. This requirement can be achieved through multiple methods, which will depend upon system architecture and design. Some commonly employed methods include: ensuring log files receive the proper file system permissions utilizing file system protections, restricting access, and backing up log data to ensure log data is retained. Network devices providing a user interface to audit data will leverage user permissions and roles identifying the user accessing the data and the corresponding rights the user enjoys in order to make access decisions regarding the deletion of audit data.

Description

Audit information includes all information (e.g., audit records, audit settings, and audit reports) needed to successfully audit information system activity. If audit data were to become compromised, then forensic analysis and discovery of the true source of potentially malicious system activity is impossible to achieve. To ensure the veracity of audit data, the network device must protect audit information from unauthorized deletion. This requirement can be achieved through multiple methods, which will depend upon system architecture and design. Some commonly employed methods include: ensuring log files receive the proper file system permissions utilizing file system protections, restricting access, and backing up log data to ensure log data is retained. Network devices providing a user interface to audit data will leverage user permissions and roles identifying the user accessing the data and the corresponding rights the user enjoys in order to make access decisions regarding the deletion of audit data.

STIG	Date
Juniper Router NDM Security Technical Implementation Guide	2018-11-14

Details

Check Text ( C-90275r2_chk )
Review the router configuration to verify that it is compliant with this requirement. The configuration example below depicts a class "JR_ENGINEER" which does not permit users belonging to the class to delete files or make changes to logging parameters. login { class JR_ENGINEER { permissions all; deny-commands "(file delete)"; deny-configuration "(system syslog)"; } } Note: The predefined classes "Operator" and "Read-only" do not have permissions to delete files. If the router is not configured to protect audit information from unauthorized deletion, this is a finding.

Check Text ( C-90275r2_chk )

Review the router configuration to verify that it is compliant with this requirement. The configuration example below depicts a class "JR_ENGINEER" which does not permit users belonging to the class to delete files or make changes to logging parameters.

login {
class JR_ENGINEER {
permissions all;
deny-commands "(file delete)";
deny-configuration "(system syslog)";
}
}

Note: The predefined classes "Operator" and "Read-only" do not have permissions to delete files.

If the router is not configured to protect audit information from unauthorized deletion, this is a finding.

Fix Text (F-97319r2_fix)
Configure one or more classes as shown in the example below whose users will not be permitted to delete files or make changes to logging parameters. [edit system] set login class JR_ENGINEER permissions all set login class JR_ENGINEER deny-configuration "(system syslog)" set login class JR_ENGINEER deny-commands “(file delete)”