TYPO3-EXT-SA-2020-010: Broken Access Control in extension "typo3_forum" (typo3_forum)

Categories: Development, Security Created by Torben Hansen
It has been discovered that the extension "typo3_forum" (typo3_forum) is susceptible to Broken Access Control.
  • Release Date: July 07, 2020
  • Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.
  • Component: typo3_forum (typo3_forum)
  • Vulnerability Type: Broken Access Control
  • Affected Versions: 1.2.0 and below
  • Severity: Medium
  • Suggested CVSS v3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:F/RL:O/RC:C
  • References: CVE-2020-15513

Problem Description

The ACL check of the extension is broken under certain conditions allowing anonymous users to create forum posts although this feature is disabled for anonymous users in the access control list.


An updated version 1.2.1 is available from the TYPO3 extension manager, Packagist and at
Users of the extension are advised to update the extension as soon as possible.


Thanks to Tobias Wegner for discovering and reporting the vulnerability and to Mittwald CM Service GmbH & Co. KG for providing an updated version of the extension.

General Advice

Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.