CVE-2024-21651 Explained : Impact and Mitigation

In this article, we will delve into the details of CVE-2024-21651, which pertains to a denial of service vulnerability in XWiki due to uncontrolled resource consumption.

Understanding CVE-2024-21651

This CVE identifies a vulnerability in XWiki that allows an attacker to execute a denial of service attack by exploiting the way the platform handles attachments.

What is CVE-2024-21651?

XWiki Platform, a versatile wiki offering services for applications, is susceptible to a denial of service exploit. An attacker with the ability to add a file to a page can upload a malicious TAR file with manipulated modification times headers. When parsed by Tika, this file can trigger excessive CPU consumption, leading to a denial of service incident.

The Impact of CVE-2024-21651

The impact of this vulnerability is rated as high, with a base severity score of 7.5. It can result in a significant impact on the availability of the XWiki platform, potentially disrupting services for users.

Technical Details of CVE-2024-21651

Let's delve deeper into the technical aspects of this vulnerability.

Vulnerability Description

The vulnerability in XWiki occurs when a user uploads a malformed TAR file with manipulated headers. This file, when processed by Tika, can cause the system to consume excessive CPU resources, leading to a denial of service condition.

Affected Systems and Versions

The following versions of XWiki are affected by this vulnerability:

xwiki-platform versions >= 14.10 and < 14.10.18
xwiki-platform versions >= 15.0-rc-1 and < 15.5.3
xwiki-platform versions >= 15.6-rc-1 and < 15.8-rc-1

Exploitation Mechanism

The attack complexity for exploiting this vulnerability is low, with a network-based attack vector. No user interaction or privileges are required for an attacker to exploit this issue.

Mitigation and Prevention

To mitigate the risks associated with CVE-2024-21651, it is essential to take immediate action and implement long-term security practices.

Immediate Steps to Take

Apply the security patches provided by XWiki in versions 14.10.18, 15.5.3, and 15.8 RC1 to prevent exploitation of this vulnerability.
Monitor system resources for any unusual spikes in CPU consumption that could indicate a denial of service attack.

Long-Term Security Practices

Regularly update XWiki to the latest stable versions to ensure that known vulnerabilities are patched promptly.
Educate users on safe attachment practices to prevent the uploading of malicious files that could exploit system vulnerabilities.

Patching and Updates

XWiki has addressed this vulnerability in versions 14.10.18, 15.5.3, and 15.8 RC1. It is crucial to apply these patches promptly to secure your XWiki platform against potential denial of service attacks.