CVE-2023-38711 Explained : Impact and Mitigation

An issue was discovered in Libreswan before 4.12 where an IKEv1 Quick Mode connection configured with ID_IPV4_ADDR or ID_IPV6_ADDR can cause a crash and restart of the pluto daemon due to a NULL pointer dereference when receiving an IDcr payload with ID_FQDN.

Understanding CVE-2023-38711

This section will provide an insight into the critical details of CVE-2023-38711.

What is CVE-2023-38711?

CVE-2023-38711 is a vulnerability found in Libreswan that can be exploited through specific configurations in IKEv1 Quick Mode connections, potentially leading to a crash and restart of the pluto daemon.

The Impact of CVE-2023-38711

The impact of this CVE includes a denial of service scenario where the pluto daemon crashes, disrupting normal operations.

Technical Details of CVE-2023-38711

In this section, we will delve into the technical aspects of the CVE.

Vulnerability Description

The vulnerability arises from a NULL pointer dereference when processing certain payloads in Libreswan versions prior to 4.12, affecting IKEv1 Quick Mode connections specifically configured with ID_IPV4_ADDR or ID_IPV6_ADDR.

Affected Systems and Versions

All Libreswan versions prior to 4.12 are affected by this vulnerability when using IKEv1 Quick Mode with specific ID configurations.

Exploitation Mechanism

The vulnerability can be exploited by sending a crafted IDcr payload with ID_FQDN to a system running an affected version of Libreswan, triggering the NULL pointer dereference.

Mitigation and Prevention

This section will outline the steps to mitigate and prevent exploitation of CVE-2023-38711.

Immediate Steps to Take

Upgrade Libreswan to version 4.12 or newer to prevent the NULL pointer dereference vulnerability.

Long-Term Security Practices

Regularly update and patch Libreswan to stay protected against known vulnerabilities and ensure proper configurations for IKEv1 Quick Mode connections.

Patching and Updates

Stay informed on security advisories from Libreswan and promptly apply any patches or updates released to address vulnerabilities.