CVE-2019-13031 Explained : Impact and Mitigation

An XML External Entity (XXE) vulnerability was discovered in LemonLDAP::NG version earlier than 1.9.20. This vulnerability occurs when submitting a notification to the notification server. The notification server is typically disabled and has a default "deny all" rule in place.

Understanding CVE-2019-13031

This section provides insights into the impact, technical details, and mitigation strategies related to CVE-2019-13031.

What is CVE-2019-13031?

CVE-2019-13031 is an XML External Entity (XXE) vulnerability found in LemonLDAP::NG versions prior to 1.9.20. It arises when sending a notification to the notification server, which is usually inactive with a default restrictive rule.

The Impact of CVE-2019-13031

The vulnerability could allow an attacker to exploit the XXE issue in LemonLDAP::NG, potentially leading to unauthorized access or sensitive data exposure.

Technical Details of CVE-2019-13031

This section delves into the specifics of the vulnerability.

Vulnerability Description

LemonLDAP::NG before 1.9.20 is susceptible to an XML External Entity (XXE) problem triggered by notification submissions to the server. The default configuration of the notification server is to deny all requests.

Affected Systems and Versions

Affected Version: LemonLDAP::NG versions earlier than 1.9.20
Systems: LemonLDAP::NG instances with the notification server enabled

Exploitation Mechanism

The vulnerability can be exploited by sending crafted XML payloads to the notification server, leveraging the XXE flaw to access sensitive information.

Mitigation and Prevention

Protecting systems from CVE-2019-13031 involves immediate actions and long-term security measures.

Immediate Steps to Take

Update LemonLDAP::NG to version 1.9.20 or later to mitigate the XXE vulnerability.
Ensure the notification server is disabled if not in use to prevent exploitation.

Long-Term Security Practices

Regularly monitor security advisories and updates for LemonLDAP::NG.
Implement secure coding practices and conduct security assessments to identify and address vulnerabilities.

Patching and Updates

Apply patches and updates provided by LemonLDAP::NG promptly to address security issues and enhance system protection.