CVE-2023-34108 : Security Advisory and Response

A critical vulnerability has been identified in mailcow affecting the Dovecot variables when handling specially crafted passwords, potentially leading to unauthorized access and security bypasses.

Understanding CVE-2023-34108

This vulnerability in mailcow allows attackers to manipulate internal Dovecot variables using crafted passwords, impacting the authentication process and potentially compromising user accounts.

What is CVE-2023-34108?

mailcow, a mail server suite based on Dovecot and other open-source software, is prone to a vulnerability that enables attackers to alter internal Dovecot variables by inserting additional key-value pairs into passwords during authentication.

The Impact of CVE-2023-34108

Exploiting this vulnerability could grant unauthorized access to user accounts, bypass security measures, and trigger unintended actions within Dovecot.

Technical Details of CVE-2023-34108

This section delves into the specific details of the vulnerability, including its description, affected systems, versions, and exploitation mechanism.

Vulnerability Description

The

passwd-verify.lua

script in mailcow is susceptible to manipulation by appending key-value pairs to crafted passwords, allowing attackers to alter the internal behavior of Dovecot.

Affected Systems and Versions

mailcow-dockerized versions prior to

2023-05a

are affected by this vulnerability, requiring immediate attention to prevent exploitation.

Exploitation Mechanism

By crafting a password with additional key-value pairs, attackers can influence the returned response from the

passwd-verify.lua

script and manipulate Dovecot's internal variables.

Mitigation and Prevention

To safeguard against potential exploits, users and administrators are encouraged to take immediate and long-term security measures.

Immediate Steps to Take

Upgrade to the patched version

2023-05a

of mailcow to mitigate the vulnerability and prevent unauthorized access to user accounts.

Long-Term Security Practices

Regularly update software, implement strong password policies, and monitor for any unauthorized changes or access to mitigate future security risks.

Patching and Updates

Stay informed about security updates and patches released by mailcow to address vulnerabilities and enhance the overall security posture.