CVE-2023-0286 Explained : Impact and Mitigation

This article provides an overview of CVE-2023-0286, a vulnerability discovered in OpenSSL that could lead to type confusion related to X.400 address processing within an X.509 GeneralName.

Understanding CVE-2023-0286

CVE-2023-0286 is a type confusion vulnerability in OpenSSL that arises from incorrect field specifications within the X.400 address parsing process, leading to potential security risks when interacting with X.509 GeneralName structures.

What is CVE-2023-0286?

The vulnerability in OpenSSL involves the misinterpretation of X.400 addresses as ASN1_STRING instead of ASN1_TYPE within the GENERAL_NAME structure. This discrepancy can be exploited by an attacker to manipulate memory pointers, potentially leading to unauthorized access to memory contents or denial of service attacks.

The Impact of CVE-2023-0286

When CRL checking is enabled, an attacker exploiting this vulnerability can leverage arbitrary pointers within a memcmp call, which can have serious consequences such as memory disclosure or disruption of services. While exploiting the vulnerability might require specific conditions, the potential impact could be severe for applications using custom CRL retrieval mechanisms over a network.

Technical Details of CVE-2023-0286

CVE-2023-0286 affects the following OpenSSL versions:

Version 3.0.0 (less than version 3.0.8)
Version 1.1.1 (less than version 1.1.1t)
Version 1.0.2 (less than version 1.0.2zg)

Vulnerability Description

The vulnerability stems from the misinterpretation of X.400 addresses within X.509 GeneralName structures, potentially allowing attackers to manipulate memory pointers leading to security compromises.

Affected Systems and Versions

OpenSSL versions 3.0.0, 1.1.1, and 1.0.2 are impacted by CVE-2023-0286.

Exploitation Mechanism

Exploiting the vulnerability requires attackers to provide both a certificate chain and a CRL, enabling them to pass arbitrary pointers and potentially execute malicious actions.

Mitigation and Prevention

To address CVE-2023-0286, immediate actions need to be taken to mitigate risks and enhance overall system security.

Immediate Steps to Take

Update OpenSSL to the latest patched versions: 3.0.8, 1.1.1t, and 1.0.2zg.
Disable CRL checking if not essential for application functionality.

Long-Term Security Practices

Regularly monitor security advisories from OpenSSL and apply patches promptly.
Implement secure coding practices to prevent similar vulnerabilities in the future.

Patching and Updates

Refer to the respective OpenSSL Advisory and git commit links for obtaining and applying the necessary patches to remediate CVE-2023-0286.
Stay informed about security updates and apply them to ensure continued protection against potential threats.