Vulnerability 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).
Check
Verify the Ubuntu operating system generates an audit record when successful/unsuccessful attempts to use the "finit_module" syscall.
Check the currently configured audit rules with the following command:
# sudo auditctl -l | grep -w finit_module
-a always,exit -F arch=b32 -S finit_module -F auid>=1000 -F auid!=-1 -k module_chng
-a always,exit -F arch=b64 -S finit_module -F auid>=1000 -F auid!=-1 -k module_chng
If the command does not return a line that matches the example or the line is commented out, this is a finding.
Notes:
For 32-bit architectures, only the 32-bit specific output lines from the commands are required.
The '-k' allows for specifying an arbitrary identifier and the string after it does not need to match the example output above.
Fix
Configure the audit system to generate an audit event for any successful/unsuccessful use of the "finit_module" syscall.
Add or update the following rules in the "/etc/audit/rules.d/stig.rules" file:
-a always,exit -F arch=b32 -S finit_module -F auid>=1000 -F auid!=4294967295 -k module_chng
-a always,exit -F arch=b64 -S finit_module -F auid>=1000 -F auid!=4294967295 -k module_chng
Notes: For 32-bit architectures, only the 32-bit specific entries are required.
The "root" account must be used to view/edit any files in the /etc/audit/rules.d/ directory.
In order to reload the rules file, issue the following command:
# sudo augenrules --load