4.1.12 Ensure use of privileged commands is collected

Information

Monitor privileged programs (those that have the setuid and/or setgid bit set on execution) to determine if unprivileged users are running these commands.

Rationale:

Execution of privileged commands by non-privileged users could be an indication of someone trying to gain unauthorized access to the system.

Solution

To remediate this issue, the system administrator will have to execute a find command to locate all the privileged programs and then add an audit line for each one of them. The audit parameters associated with this are as follows:
-F path=' $1 ' - will populate each file name found through the find command and processed by awk. -F perm=x - will write an audit record if the file is executed. -F auid>=1000 - will write a record if the user executing the command is not a privileged user. -F auid!= 4294967295 - will ignore Daemon events
All audit records should be tagged with the identifier 'privileged'.
Run the following command replacing with a list of partitions where programs can be executed from on your system:

# find <partition> -xdev ( -perm -4000 -o -perm -2000 ) -type f | awk '{print
'-a always,exit -F path=' $1 ' -F perm=x -F auid>=1000 -F auid!=4294967295
-k privileged' }'

Add all resulting lines to the /etc/audit/audit.rules file.

Impact:

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

Notes:

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

References: 800-53|AU-12, CSCv7|6.3

Plugin: Unix

Control ID: 14475ef9b93accd139d7ed70e004505b691abee6a8d90f9a835e51810433e4fb