--- title: "TYPO3-EXT-SA-2020-010: Broken Access Control in extension \"typo3_forum\" (typo3_forum)" url: "https://news.typo3.com/security/advisory/typo3-ext-sa-2020-010" description: "It has been discovered that the extension \"typo3_forum\" (typo3_forum) is susceptible to Broken Access Control." image: "https://news.typo3.com/_assets/d1e01514e4c4a5b3147940fa2ec50682/Images/og-image-news.jpg" date: 2026-06-11 modified: 2026-06-11 categories: - "Developer & Technology" - TYPO3 Extensions --- # TYPO3-EXT-SA-2020-010: Broken Access Control in extension "typo3_forum" (typo3_forum) - [Developer & Technology](https://news.typo3.com/article/category/developer-technology) - Security / [TYPO3 Extensions](https://news.typo3.com/article/category/security/typo3-extensions) TYPO3-EXT-SA-2020-010: Broken Access Control in extension "typo3\_forum" (typo3\_forum) ======================================================================================= 07 July 2020 ![A laptop screen displaying a list of security advisories](https://news.typo3.com/typo3temp/assets/_processed_/d/c/csm_security_blog_default_77f8e86036.webp) It has been discovered that the extension "typo3\_forum" (typo3\_forum) is susceptible to Broken Access Control. - ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/e4eaa13e33dd086a9c06f2570cb34609.jpeg)[Torben Hansen](https://news.typo3.com/article/author/torben-hansen) - 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](https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:F/RL:O/RC:C&version=3.1) - References: [CVE-2020-15513](https://cve.mitre.org/cgi-bin/cvename.cgi?name=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. ### Solution 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. ### Credits 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](https://docs.typo3.org/typo3cms/CoreApiReference/Security/Index.html#security-guidelines). Please subscribe to the [typo3-announce](http://lists.typo3.org/cgi-bin/mailman/listinfo/typo3-announce) mailing list. ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/7cf52722a5b7183b29d378a2284bd103.jpeg) About the Author [Torben Hansen](https://news.typo3.com/article/author/torben-hansen) Open Source Enthusiast & TYPO3 Expert I’m a passionate open-source advocate and dedicated TYPO3 expert. As a freelancer, I offer professional TYPO3 services to clients while actively contributing to the TYPO3 ecosystem. I have developed several public TYPO3 extensions and serve as the Co-Lead of the TYPO3 Security Team, helping to enhance the platform’s security and functionality. For many years, I have been blogging about TYPO3, sharing insights and expertise with the community. [More posts by this author](https://news.typo3.com/article/author/torben-hansen)