cyberstrikeus CIS Ubuntu Linux 18.04 LTS Benchmark v2.2.0 - Control 4.3.6
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Description
sudo caches credentials for a period of time. The default timeout for the sudo command is 15 minutes. It is recommended that the timeout be set to no more than 15 minutes.
Rationale
If the timeout is too long, a user could execute commands as root for an extended period without re-authenticating. This could allow unauthorized users to execute commands as root if the original user walks away from their terminal.
Audit Procedure
Command Line
Run the following command to verify the sudo authentication timeout:
grep -roP "timestamp_timeout\h*=\h*\d+" /etc/sudoers /etc/sudoers.d/
Expected Result
If output is returned, timestamp_timeout should be 15 or less. If no output is returned, the default of 15 minutes is in effect, which is compliant.
Remediation
Command Line
Edit the file /etc/sudoers or a file in /etc/sudoers.d/ with visudo and set or modify the timestamp_timeout value:
Defaults timestamp_timeout=15
OR set to a value of 15 or less per site policy.
Default Value
timestamp_timeout=15
References
- NIST SP 800-53 Rev. 5: IA-11
CIS Controls
v8 - 5.4 Restrict Administrator Privileges to Dedicated Administrator Accounts.
v7 - 4.3 Ensure the Use of Dedicated Administrative Accounts.
Profile Applicability
- Level 1 - Server
- Level 1 - Workstation
Assessment Status
Automated