CVE-2021-42096 Explained : Impact and Mitigation

GNU Mailman before 2.1.35 may allow remote Privilege Escalation through a certain csrf_token value derived from the admin password.

Understanding CVE-2021-42096

What is CVE-2021-42096?

GNU Mailman before version 2.1.35 is vulnerable to remote Privilege Escalation. An attacker could potentially exploit a certain csrf_token value that is based on the admin password, enabling them to launch a brute-force attack to guess the password.

The Impact of CVE-2021-42096

This vulnerability could lead to unauthorized access to the Mailman admin account, potentially compromising the integrity and confidentiality of the mailing list system.

Technical Details of CVE-2021-42096

Vulnerability Description

An insecure derivation of the csrf_token value from the admin password in GNU Mailman before version 2.1.35 may result in a security flaw that allows remote Privilege Escalation.

Affected Systems and Versions

Affected System: GNU Mailman
Affected Version: before 2.1.35

Exploitation Mechanism

The vulnerability stems from a certain csrf_token value being tied to the admin password, creating an opening for attackers to perform a brute-force attack.

Mitigation and Prevention

Immediate Steps to Take

Update Mailman to version 2.1.35 or later to mitigate the vulnerability.
Monitor the mailing list system for any unauthorized access or suspicious activities.
Regenerate the csrf_token value based on secure randomness instead of the admin password.

Long-Term Security Practices

Regularly review and update security configurations for the mailing list software.
Implement strong password policies for admin accounts to prevent brute-force attacks.

Patching and Updates

Apply security patches and updates provided by GNU Mailman promptly to address known vulnerabilities.