CVE-2023-4807 : Vulnerability Insights and Analysis

This article provides detailed information on CVE-2023-4807, a vulnerability in the POLY1305 MAC implementation in the OpenSSL library that may potentially corrupt the internal state of applications running on Windows 64 platform.

Understanding CVE-2023-4807

This section delves into the specifics of the CVE-2023-4807 vulnerability, outlining its impacts and technical details.

What is CVE-2023-4807?

The CVE-2023-4807 vulnerability pertains to a bug in the POLY1305 MAC implementation in OpenSSL, which can lead to corruption of the internal application state on Windows 64 platform when running on newer X86_64 processors supporting AVX512-IFMA instructions. This issue arises from the failure to save the contents of non-volatile XMM registers during MAC calculation, resulting in potential consequences for applications utilizing the OpenSSL library.

The Impact of CVE-2023-4807

If an attacker can manipulate the use of the POLY1305 MAC algorithm in an application utilizing OpenSSL, the application's state may be compromised, leading to varied application-dependent outcomes. The vulnerability primarily affects newer x86_64 processors with AVX512-IFMA instructions, potentially allowing attackers to gain control over the application process or cause denial of service through incorrect calculation results or crashes.

Technical Details of CVE-2023-4807

This section provides a deeper dive into the vulnerability's technical aspects, including its description, affected systems, and exploitation mechanism.

Vulnerability Description

The issue lies in the failure to save non-volatile XMM registers during MAC calculation on Windows 64 platform, affecting applications dependent on these registers for proper operation. The vulnerability is specific to newer x86_64 processors supporting AVX512-IFMA instructions, potentially exposing applications to manipulation by malicious actors.

Affected Systems and Versions

The vulnerability impacts OpenSSL versions 1.1.1 (less than 1.1.1w), 3.0.0 (less than 3.0.11), and 3.1.0 (less than 3.1.3) on the Windows 64 platform when running on newer X86_64 processors with AVX512-IFMA instructions.

Exploitation Mechanism

By influencing the use of the POLY1305 MAC algorithm in OpenSSL, attackers can trigger the corruption of application state on Windows 64 platform, potentially leading to unauthorized control over the application process or denial of service.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-4807, it is crucial to implement immediate steps and adopt long-term security practices to enhance system defense and integrity.

Immediate Steps to Take

Disable the AVX512-IFMA instructions support at runtime by configuring the environment variable OPENSSL_ia32cap to ":~0x200000". This workaround can help prevent exploitation of the vulnerability until a patch is applied.

Long-Term Security Practices

Ensure regular security updates and patches for the OpenSSL library to address vulnerabilities promptly and maintain system security against potential threats.

Patching and Updates

Monitor official advisories from OpenSSL, apply recommended patches such as versions 1.1.1w, 3.0.11, and 3.1.3, and stay informed about security best practices to safeguard systems from CVE-2023-4807 and similar vulnerabilities.