Attack Chain

1. The attacker gains initial access to the system via an unspecified method (e.g., compromised account, physical access).
2. The attacker identifies a vulnerable version of sudo installed on the system.
3. The attacker crafts a malicious sudo command or exploits a configuration flaw to leverage one of the vulnerabilities.
4. Sudo executes the malicious command with elevated privileges due to the vulnerability.
5. The attacker uses the elevated privileges to modify system files or execute commands as root.
6. The attacker installs a backdoor or creates a new privileged account for persistent access.
7. The attacker uses the escalated privileges to access sensitive data or perform other malicious actions.

Impact

Successful exploitation of these vulnerabilities allows a local attacker to gain complete control of the affected system. This can lead to data theft, system corruption, or the installation of malware. The number of potential victims is dependent on the number of systems running vulnerable versions of sudo.

Recommendation

• Monitor process creations for unexpected sudo usage patterns, especially commands run with root privileges that deviate from normal administrative tasks. (See Sigma rule “Detect Suspicious Sudo Usage”).
• Enable audit logging for sudo to capture detailed information about command execution.
• Regularly update sudo to the latest version to patch known vulnerabilities.