Multiple XSS flaws in Joomla can lead to remote code execution

Joomla maintainers have addressed multiple vulnerabilities in the popular content management system (CMS) that can lead to execute arbitrary code.

The maintainers of the Joomla! Project released Joomla 5.0.3 and 4.4.3 versions that addressed the following vulnerabilities in the popular content management system (CMS):

• [20240201] –CVE-2024-21722 Core – Insufficient session expiration in MFA management views: The MFA management features did not properly terminate existing user sessions when a user’s MFA methods have been modified
• [20240202] – CVE-2024-21723 Core – Open redirect in installation application: Inadequate parsing of URLs could result into an open redirect.
• [20240203] – CVE-2024-21724 Core – XSS in media selection fields: Inadequate input validation for media selection fields lead to XSS vulnerabilities in various extensions.
• [20240204] – CVE-2024-21725 Core – XSS in mail address outputs: Inadequate escaping of mail addresses lead to XSS vulnerabilities in various components.
• [20240205] – CVE-2024-21726 Core – Inadequate content filtering within the filter code: Inadequate content filtering leads to XSS vulnerabilities in various components. 

The impact of these flaws can be widespread because roughly 2% of all websites use Joomla, millions of websites worldwide use this CMS.

“The widespread usage of Joomla and the fact that most deployments are publicly accessible makes it a valuable target for threat actors. Just recently, Joomla was targeted in an attack against different organizations via an improper access control vulnerability (CVE-2023-23752).” reported cybersecurity firm Sonarsource which discovered an issue that led to the XSS vulnerabilities in the popular Content Management System.

The researchers pointed out that an attacker can exploit these issues to gain remote code execution by tricking an administrator into clicking on a malicious link.

“While we won’t be disclosing technical details at this time, we want to emphasize the importance of prompt action to mitigate this risk. We strongly advise all Joomla users to update to the latest version. The first release known to address the vulnerability is Joomla version 5.0.3/4.4.3.” states Sonarsource which did not disclose technical details about the issues to avoid massive exploitation in the wild.

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Pierluigi Paganini

(SecurityAffairs – hacking, Joomla)