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 <partition> 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/rules.d/audit.rules file.

See Also

https://workbench.cisecurity.org/files/2449

Item Details

Category: AUDIT AND ACCOUNTABILITY

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

Plugin: Unix

Control ID: 1254eaa9bba137b03fb14ac4075e4f6898f8d1f4f162d951074700fff6c5e28c