8.1.12 Collect Use of Privileged Commands

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.

NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.

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>=500 - will write a record if the user executing the command is not a privileged user.

-F auid!= 4294967295 - will ignore Daemon eventsAll audit records will be tagged with the identifier 'privileged.'

# find PART -xdev ( -perm -4000 -o -perm -2000 ) -type f | awk '{print "-a always,exit -F path=" $1 " -F perm=x -F auid>=500 -F auid!=4294967295 -k privileged" }'

Next, add those lines to the /etc/audit/audit.rules file.

See Also

https://workbench.cisecurity.org/files/91

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-12c.

Plugin: Unix

Control ID: 327b0428f6fe67dd6d4291a356f987046c41d3368661a28de7a60cabf5ad62d5