CVE-2023-5330 : What You Need to Know

This CVE was assigned by Mattermost and published on October 9, 2023. It affects Mattermost versions up to 8.1.1 and allows attackers to launch a Denial of Service attack via Opengraph data cache.

Understanding CVE-2023-5330

This vulnerability in Mattermost could lead to a server becoming unavailable due to an attacker's ability to fill the cache by sending a specially crafted request to /api/v4/opengraph.

What is CVE-2023-5330?

The CVE-2023-5330 vulnerability in Mattermost arises from the failure to enforce a limit on the size of the cache entry for Opengraph data. This oversight enables attackers to disrupt server availability by filling up the cache through malicious requests.

The Impact of CVE-2023-5330

With a CVSS base score of 4.3 and a base severity of MEDIUM, the impact of this vulnerability is noteworthy. While the attack complexity is low, the availability impact is also considered low. However, the potential for turning the server unavailable raises concerns for affected systems.

Technical Details of CVE-2023-5330

The vulnerability stems from uncontrolled resource consumption (CWE-400) due to the lack of limits on cache entry size for Opengraph data. Affected versions include Mattermost up to 8.1.1.

Vulnerability Description

Mattermost fails to enforce a limit on the size of the cache entry for Opengraph data, allowing attackers to disrupt server availability by filling the cache via specially crafted requests to /api/v4/opengraph.

Affected Systems and Versions

Versions of Mattermost up to 8.1.1 are impacted by this vulnerability. Specifically, versions 7.8.10, 8.0.2, and 8.1.1 are affected, while versions 7.8.11, 8.0.3, and 8.1.2 are unaffected.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending malicious requests to /api/v4/opengraph, causing the cache to be filled with crafted data and rendering the server unavailable.

Mitigation and Prevention

To address CVE-2023-5330 and prevent potential Denial of Service attacks, immediate steps should be taken to secure Mattermost servers and ensure long-term security practices are in place.

Immediate Steps to Take

Update Mattermost Server to versions 7.8.11, 8.0.3, 8.1.2, or higher to mitigate the vulnerability and prevent the risk of a Denial of Service attack.

Long-Term Security Practices

It is advisable to regularly update systems and software, implement secure coding practices, conduct security assessments, and stay informed about potential vulnerabilities to enhance overall cybersecurity posture.

Patching and Updates

Staying current with software patches and updates, especially security patches provided by Mattermost, is crucial for addressing known vulnerabilities and maintaining a secure environment. Regularly monitoring security advisories and promptly applying patches is essential for mitigating risk and protecting against potential exploits.