CVE-2023-2193 : Security Advisory and Response

This CVE record, assigned by Mattermost, highlights a vulnerability where existing authorization codes are not invalidated when deauthorizing an OAuth2 app, enabling attackers with possession of an authorization code to create an access token.

Understanding CVE-2023-2193

This section delves into the critical aspects of the CVE-2023-2193 vulnerability.

What is CVE-2023-2193?

The vulnerability in Mattermost occurs due to the failure to invalidate existing authorization codes during the deauthorization process of an OAuth2 app. This oversight allows malicious actors in possession of an authorization code to exploit it for generating an access token, potentially leading to unauthorized access.

The Impact of CVE-2023-2193

The impact of this vulnerability is rated as MEDIUM in severity with a CVSS v3.1 base score of 6.5. It poses a high risk to confidentiality and integrity, with a requirement of high privileges for exploitation and a low attack complexity. The availability impact is assessed as none.

Technical Details of CVE-2023-2193

This section provides a deeper insight into the technical aspects of the CVE-2023-2193 vulnerability.

Vulnerability Description

The vulnerability arises from Mattermost's failure to revoke existing authorization codes post deauthorization of an OAuth2 app, facilitating unauthorized access through the creation of access tokens by threat actors.

Affected Systems and Versions

The CVE-2023-2193 vulnerability impacts Mattermost versions up to and including 7.9.1. Versions 7.1.7, 7.7.3, 7.8.2, and 7.9.1 are confirmed to be affected, while versions 7.1.9, 7.7.5, 7.8.4, and 7.9.3 are unaffected.

Exploitation Mechanism

Attack vectors for exploiting this vulnerability involve network-based attacks with high privileges required to initiate malicious actions. The vulnerability poses a serious threat to the confidentiality and integrity of affected systems.

Mitigation and Prevention

Understanding the steps to mitigate and prevent the CVE-2023-2193 vulnerability is crucial for ensuring system security.

Immediate Steps to Take

To address this vulnerability, it is recommended to update Mattermost to the latest version, specifically v7.10, v7.9.3, v7.8.4, v7.7.5, v7.1.9, or any higher version that includes the necessary security patches.

Long-Term Security Practices

Implementing robust security practices, such as regular security audits, access control measures, and ongoing monitoring, can help prevent similar security vulnerabilities in the future.

Patching and Updates

Regularly applying security patches and updates provided by Mattermost is essential to mitigate the risk of exploitation related to CVE-2023-2193. Stay informed about security advisories and promptly apply recommended updates to ensure the security of your system.