CVE-2023-41378 : Security Advisory and Response

A detailed overview of CVE-2023-41378 highlighting the vulnerability, impact, technical details, and mitigation steps.

Understanding CVE-2023-41378

This section explores the critical aspects of CVE-2023-41378.

What is CVE-2023-41378?

CVE-2023-41378 describes a vulnerability in Calico Typha and Calico Enterprise Typha, allowing an unclean TLS handshake to block the server indefinitely, leading to a denial of service.

The Impact of CVE-2023-41378

The vulnerability can result in a client TLS handshake blocking the Calico Typha server indefinitely, causing a denial of service. This could lead to severe availability issues.

Technical Details of CVE-2023-41378

This section delves into the specifics of the vulnerability.

Vulnerability Description

During certain conditions, the TLS Handshake() call can block the main server handle for loop without any timeout, allowing an unclean TLS handshake to hang indefinitely, affecting server operation and other connections.

Affected Systems and Versions

Calico Typha versions v3.26.2, v3.25.1, and below, as well as Calico Enterprise Typha versions v3.17.1, v3.16.3, v3.15.3, and below, are impacted by this vulnerability.

Exploitation Mechanism

The client TLS handshake blocking the main server loop indefinitely leads to a state where other connections wait for the handshake to finish, causing a denial of service.

Mitigation and Prevention

Explore steps to mitigate and prevent the CVE-2023-41378 vulnerability.

Immediate Steps to Take

Implement a patch or workaround provided by the vendor to address the TLS handshake issue and prevent service disruption.

Long-Term Security Practices

Enhance security measures by regularly updating and monitoring network security configurations to detect and prevent similar vulnerabilities.

Patching and Updates

Apply the necessary patches released by the vendor to fix the TLS handshake vulnerability in affected versions.