Detections
Analytics

1.160 OL09-00-000845

Information

OL 9 must be configured so that successful/unsuccessful uses of the umount2 system call generate an audit record.

GROUP ID: V-271595
RULE ID: SV-271595r1155316

The changing of file permissions could indicate that a user is attempting to gain access to information that would otherwise be disallowed. Auditing discretionary access control (DAC) modifications can facilitate the identification of patterns of abuse among both authorized and unauthorized users.

Satisfies: SRG-OS-000037-GPOS-00015, 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 successful/unsuccessful use of the umount2 system call by adding the following rules to a rules file in /etc/audit/rules.d/ directory: (Example /etc/audit/rules.d/audit.rules)

-a always,exit -F arch=b32 -S umount2 -F auid>=1000 -F auid!=unset -k perm_mod
-a always,exit -F arch=b64 -S umount2 -F auid>=1000 -F auid!=unset -k perm_mod

The audit daemon must be restarted for the changes to take effect.

Restart auditd:

$ sudo service auditd restart

See Also

https://workbench.cisecurity.org/benchmarks/27024

Item Details

Category: AUDIT AND ACCOUNTABILITY, MAINTENANCE

References: 800-53|AU-3, 800-53|AU-12a., 800-53|AU-12c., 800-53|MA-4(1), CCI|CCI-000130, CCI|CCI-000169, CCI|CCI-000172, CCI|CCI-002884, Rule-ID|SV-271595r1155316_rule, STIG-ID|OL09-00-000845, Vuln-ID|V-271595

Plugin: Unix

Control ID: 3d2d52282e3f65ba958070eec5ed74ff79792bd43ccfc0b9132befcc2be15811