CVE-2023-38710 : What You Need to Know

An issue was discovered in Libreswan before 4.12 that can lead to a denial of service (DoS) attack when handling IKEv2 Child SA REKEY packets with an invalid IPsec protocol ID number. This vulnerability could cause the pluto daemon to crash and restart, affecting the availability of the service.

Understanding CVE-2023-38710

The vulnerability in Libreswan allows an attacker to trigger a DoS condition by sending a malicious IKEv2 Child SA REKEY packet with an invalid IPsec protocol ID number.

What is CVE-2023-38710?

The issue in Libreswan before version 4.12 involves a validation error in handling IKEv2 Child SA REKEY packets with incorrect IPsec protocol ID numbers, leading to a denial of service.

The Impact of CVE-2023-38710

Exploitation of this vulnerability could result in a crash of the pluto daemon, disrupting the availability of the service and potentially causing service interruptions.

Technical Details of CVE-2023-38710

The technical details of the CVE-2023-38710 vulnerability are as follows:

Vulnerability Description

When processing IKEv2 Child SA REKEY packets with an invalid IPsec protocol ID number, an error notify of INVALID_SPI is returned, causing the pluto daemon to crash and restart.

Affected Systems and Versions

The vulnerability affects versions of Libreswan prior to 4.12, with the earliest impacted version cited as 3.20. All systems running these versions are at risk.

Exploitation Mechanism

By sending a specifically crafted IKEv2 Child SA REKEY packet with an incorrect IPsec protocol ID number of 0 or 1, an attacker can exploit this vulnerability to trigger a DoS condition.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-38710, follow these steps:

Immediate Steps to Take

Update Libreswan to version 4.12 or newer to eliminate the vulnerability.
Monitor network traffic for any signs of malicious IKEv2 Child SA REKEY packets.

Long-Term Security Practices

Regularly update software and security patches to stay protected against known vulnerabilities.
Implement network segmentation and access control to limit the impact of potential attacks.

Patching and Updates

Stay informed about security advisories and updates from the Libreswan project. Apply patches promptly to ensure your systems are protected against emerging threats.