Details

sudo can be configured to run only from a pseudo-pty

Note: visudo edits the sudoers file in a safe fashion, analogous to vipw(8). visudo locks the sudoers file against multiple simultaneous edits, provides basic sanity checks, and checks for parse errors. If the sudoers file is currently being edited you will receive a message to try again later. The -f option allows you to tell visudo which file to edit.

Rationale:

Attackers can run a malicious program using sudo, which would again fork a background process that remains even when the main program has finished executing.

This can be mitigated by configuring sudo to run other commands only from a pseudo-pty, whether I/O logging is turned on or not.

Solution

Edit the file /etc/sudoers or a file in /etc/sudoers.d/ with visudo or visudo -f and add the following line:

Defaults use_pty

Supportive Information

The following resource is also helpful.

• https://workbench.cisecurity.org/files/3682

This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management, Identification and Authentication.This control applies to the following type of system Unix.

References

• 800-53|CM-1
• 800-53|CM-2
• 800-53|CM-6
• 800-53|CM-7
• 800-53|IA-5
• CSCv7|4

Source

• Tenable.com/audits