CVE-2019-18684 : Exploit Details and Defense Strategies

Sudo version 1.8.29 has a vulnerability that allows local users to gain root access by exploiting a race condition in the sudo process. This vulnerability is disputed due to the permissions required to exploit it.

Understanding CVE-2019-18684

This CVE involves a vulnerability in Sudo version 1.8.29 that can potentially allow local users to escalate privileges to root level.

What is CVE-2019-18684?

Sudo 1.8.29 vulnerability enables local users to gain root access by writing to file descriptor 3 of the sudo process.
The vulnerability arises from a race condition during user ID determination and system calls.
Attackers can exploit this by writing specific commands to a file while Sudo is requesting a password.

The Impact of CVE-2019-18684

Local users can potentially escalate privileges to root level if they can write to file descriptor 3 of the sudo process.
The vulnerability's severity is disputed due to the debate around necessary permissions for successful exploitation.

Technical Details of CVE-2019-18684

This section provides detailed technical insights into the vulnerability.

Vulnerability Description

Sudo version 1.8.29 vulnerability allows local users to gain root access by manipulating file descriptor 3.
The vulnerability is attributed to a race condition between user ID determination and system calls.

Affected Systems and Versions

Sudo version 1.8.29 is affected by this vulnerability.
The specific versions impacted are those up to and including 1.8.29.

Exploitation Mechanism

Attackers exploit the vulnerability by writing specific commands to file descriptor 3 while Sudo is prompting for a password.
Successful exploitation depends on permissions to write to /proc/#####/fd/3 and /etc/sudoers.

Mitigation and Prevention

Protecting systems from CVE-2019-18684 requires immediate actions and long-term security practices.

Immediate Steps to Take

Monitor and restrict access to file descriptor 3 of the sudo process.
Regularly review and update permissions for /proc/#####/fd/3 and /etc/sudoers.

Long-Term Security Practices

Implement the principle of least privilege to limit user access.
Conduct regular security audits and vulnerability assessments.

Patching and Updates

Apply patches and updates provided by Sudo to address the vulnerability.