Title

Successful/unsuccessful uses of the mount syscall in RHEL 8 must generate an audit record. (Cat II impact)

Discussion

Without generating audit records that are specific to the security and mission needs of the organization, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. Audit records can be generated from various components within the information system (e.g., module or policy filter). The "mount" syscall is used to mount a filesystem. When a user logs on, the AUID is set to the UID of the account that is being authenticated. Daemons are not user sessions and have the loginuid set to "-1". The AUID representation is an unsigned 32-bit integer, which equals "4294967295". The audit system interprets "-1", "4294967295", and "unset" in the same way. Satisfies: SRG-OS-000062-GPOS-00031, SRG-OS-000037-GPOS-00015, SRG-OS-000042-GPOS-00020, SRG-OS-000062-GPOS-00031, SRG-OS-000392-GPOS-00172, SRG-OS-000462-GPOS-00206, SRG-OS-000471-GPOS-00215

Check Content

Verify that an audit event is generated for any successful/unsuccessful use of the "mount" syscall by performing the following command to check the file system rules in "/etc/audit/audit.rules": $ sudo grep -w "\-S mount" /etc/audit/audit.rules -a always,exit -F arch=b32 -S mount -F auid>=1000 -F auid!=unset -k privileged-mount -a always,exit -F arch=b64 -S mount -F auid>=1000 -F auid!=unset -k privileged-mount If the command does not return a line, or the line is commented out, this is a finding.

Fix Text

Configure the audit system to generate an audit event for any successful/unsuccessful use of the "mount" syscall by adding or updating the following rules in the "/etc/audit/rules.d/audit.rules" file: -a always,exit -F arch=b32 -S mount -F auid>=1000 -F auid!=unset -k privileged-mount -a always,exit -F arch=b64 -S mount -F auid>=1000 -F auid!=unset -k privileged-mount The audit daemon must be restarted for the changes to take effect.

Additional Identifiers

Rule ID: SV-230425r1017226_rule

Vulnerability ID: V-230425

Group Title: SRG-OS-000062-GPOS-00031

Expert Comments

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