STIGQter: STIG Summary: Canonical Ubuntu 20.04 LTS Security Technical Implementation Guide Version: 1 Release: 1 Benchmark Date: 10 Mar 2021:

The Ubuntu operating system must prevent all software from executing at higher privilege levels than users executing the software and the audit system must be configured to audit the execution of privileged functions.

DISA Rule

SV-238304r654087_rule

Vulnerability Number

V-238304

Group Title

SRG-OS-000326-GPOS-00126

Rule Version

UBTU-20-010211

Severity

CAT II

CCI(s)

• CCI-002233 - The information system prevents organization-defined software from executing at higher privilege levels than users executing the software.
• CCI-002234 - The information system audits the execution of privileged functions.

Weight

10

Fix Recommendation

Configure the Ubuntu operating system to audit the execution of all privileged functions.

Add or update the following rules in the "/etc/audit/rules.d/stig.rules" file:

-a always,exit -F arch=b64 -S execve -C uid!=euid -F euid=0 -F key=execpriv
-a always,exit -F arch=b64 -S execve -C gid!=egid -F egid=0 -F key=execpriv
-a always,exit -F arch=b32 -S execve -C uid!=euid -F euid=0 -F key=execpriv
-a always,exit -F arch=b32 -S execve -C gid!=egid -F egid=0 -F key=execpriv

Notes: For 32-bit architectures, only the 32-bit specific entries are required.

To reload the rules file, issue the following command:

$ sudo augenrules --load

Check Contents

Verify the Ubuntu operating system audits the execution of privilege functions by auditing the "execve" system call.

Check the currently configured audit rules with the following command:

$ sudo auditctl -l | grep execve

-a always,exit -F arch=b64 -S execve -C uid!=euid -F euid=0 -F key=execpriv
-a always,exit -F arch=b64 -S execve -C gid!=egid -F egid=0 -F key=execpriv
-a always,exit -F arch=b32 -S execve -C uid!=euid -F euid=0 -F key=execpriv
-a always,exit -F arch=b32 -S execve -C gid!=egid -F egid=0 -F key=execpriv

If the command does not return lines that match the example or the lines are 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.

Vulnerability Number

V-238304

Documentable

False

Rule Version

UBTU-20-010211

Severity Override Guidance

Verify the Ubuntu operating system audits the execution of privilege functions by auditing the "execve" system call.

Check the currently configured audit rules with the following command:

$ sudo auditctl -l | grep execve

-a always,exit -F arch=b64 -S execve -C uid!=euid -F euid=0 -F key=execpriv
-a always,exit -F arch=b64 -S execve -C gid!=egid -F egid=0 -F key=execpriv
-a always,exit -F arch=b32 -S execve -C uid!=euid -F euid=0 -F key=execpriv
-a always,exit -F arch=b32 -S execve -C gid!=egid -F egid=0 -F key=execpriv

If the command does not return lines that match the example or the lines are 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.

Check Content Reference

M

Target Key

5318

Comments