4.1.14 Ensure file deletion events by users are collected - delete x64

Information

Monitor the use of system calls associated with the deletion or renaming of files and file attributes. This configuration statement sets up monitoring for the unlink (remove a file), unlinkat (remove a file attribute), rename (rename a file) and renameat (rename a file attribute) system calls and tags them with the identifier 'delete'.

Rationale:

Monitoring these calls from non-privileged users could provide a system administrator with evidence that inappropriate removal of files and file attributes associated with protected files is occurring. While this audit option will look at all events, system administrators will want to look for specific privileged files that are being deleted or altered.

Solution

For 32 bit systems add the following lines to the /etc/audit/audit.rules file:

-a always,exit -F arch=b32 -S unlink -S unlinkat -S rename -S renameat -F auid>=1000 -F auid!=4294967295 -k delete

For 64 bit systems add the following lines to the /etc/audit/audit.rules file:

-a always,exit -F arch=b64 -S unlink -S unlinkat -S rename -S renameat -F auid>=1000 -F auid!=4294967295 -k delete
-a always,exit -F arch=b32 -S unlink -S unlinkat -S rename -S renameat -F auid>=1000 -F auid!=4294967295 -k delete

Impact:

Auditing can produce a large amount of information, creating large and/or many audit log files.

Notes:

At a minimum, configure the audit system to collect file deletion events for all users and root.

Reloading the auditd config to set active settings may require a system reboot.

See Also

https://workbench.cisecurity.org/files/2619

Item Details

Category: AUDIT AND ACCOUNTABILITY, SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|AU-3, 800-53|AU-12, 800-53|SC-7(10), CSCv7|6.2, CSCv7|13

Plugin: Unix

Control ID: 50da770c84a06555a46d6680b87395a0b151299e23c043f2dd63086eb2f659b5