Detections
Analytics

1.241 OL08-00-030311

Information

OL 8 must generate audit records for any use of the "postdrop" command.

GROUP ID: V-248762
RULE ID: SV-248762r958412

Reconstruction of harmful events or forensic analysis is not possible if audit records do not contain enough information.

At a minimum, the organization must audit the full-text recording of privileged commands. The organization must maintain audit trails in sufficient detail to reconstruct events to determine the cause and impact of compromise. The "postdrop" command creates a file in the maildrop directory and copies its standard input to the file.

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-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

Solution

Configure the audit system to generate an audit event for any use of the "postdrop" command by adding or updating the following rule in the "/etc/audit/rules.d/audit.rules" file:

-a always,exit -F path=/usr/sbin/postdrop -F perm=x -F auid>=1000 -F auid!=unset -k privileged-unix-update

The audit daemon must be restarted for the changes to take effect. To restart the audit daemon, run the following command:

$ sudo service auditd restart

See Also

https://workbench.cisecurity.org/benchmarks/23791

Item Details

Category: AUDIT AND ACCOUNTABILITY, MAINTENANCE

References: 800-53|AU-3, 800-53|AU-3(1), 800-53|AU-12a., 800-53|AU-12c., 800-53|MA-4(1), CAT|II, CCI|CCI-000130, CCI|CCI-000135, CCI|CCI-000169, CCI|CCI-000172, CCI|CCI-002884, Rule-ID|SV-248762r958412_rule, STIG-ID|OL08-00-030311, Vuln-ID|V-248762

Plugin: Unix

Control ID: 943e1a296b60fb0562bcb59abe12f12f6f990d5ed82a86b729cdb8dbfcbd1172