Thorsten PhpMyfaq up to 4.1.x Template html_entity_decode cross site scripting

Summaryinfo

A vulnerability identified as problematic has been detected in Thorsten PhpMyfaq up to 4.1.x. This issue affects the function html_entity_decode of the component Template. This manipulation causes cross site scripting. The identification of this vulnerability is CVE-2026-56736. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Thorsten PhpMyfaq up to 4.1.x and classified as problematic. Affected by this vulnerability is the function html_entity_decode of the component Template. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

phpMyFAQ is an open source FAQ web application. A stored cross-site scripting (XSS) vulnerability in versions prior to 4.2.0-alpha allows any unauthenticated user (or low-privileged registered user) to inject arbitrary JavaScript that executes in an administrator's browser when they review or edit a user-submitted FAQ entry. This leads to admin account takeover via session theft. The vulnerability exists because `html_entity_decode()` converts HTML entities into executable HTML after `strip_tags()` has already passed them through, and the admin template renders the content with Twig's `|raw` filter without any output sanitization. Version 4.2.0-alpha fixes the issue.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-56736 since 06/22/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 4.2.0-alpha eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Content Management System

Vendor

• Thorsten

Name

• PhpMyfaq

Version

• 4.0
• 4.1

License

• open-source

Website

• Product: https://github.com/thorsten/phpMyFAQ/

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• 🔒

CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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