SB2026040131 - Multiple vulnerabilities in Joomla!



SB2026040131 - Multiple vulnerabilities in Joomla!

Published: April 1, 2026

Security Bulletin ID SB2026040131
Severity
High
Patch available
YES
Number of vulnerabilities 6
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 33% Medium 33% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 6 secuirty vulnerabilities.


1) Improper access control (CVE-ID: CVE-2026-21629)

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions in com_ajax. A remote attacker can bypass implemented security restrictions and gain unauthorized access to the application.


2) Improper access control (CVE-ID: CVE-2026-23899)

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions in webservice endpoints. A remote attacker can bypass implemented security restrictions and gain unauthorized access to the application.


3) External Control of File Name or Path (CVE-ID: CVE-2026-23898)

The vulnerability allows a remote attacker to delete arbitrary files.

The vulnerability exists due to application allows an attacker to control path of the files to delete in com_joomlaupdate. A remote attacker can delete arbitrary files on the system.


4) Cross-site scripting (CVE-ID: CVE-2026-21632)

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data in various article title outputs. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.


5) Cross-site scripting (CVE-ID: CVE-2026-21631)

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data in com_associations comparison view. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.


6) SQL injection (CVE-ID: CVE-2026-21630)

The vulnerability allows a remote attacker to execute arbitrary SQL queries in database.

The vulnerability exists due to insufficient sanitization of user-supplied data in com_content articles webservice endpoint. A remote attacker can send a specially crafted request to the affected application and execute arbitrary SQL commands within the application database.

Successful exploitation of this vulnerability may allow a remote attacker to read, delete, modify data in database and gain complete control over the affected application.


Remediation

Install update from vendor's website.