--- title: "TYPO3-EXT-SA-2021-008: Sensitive Information Disclosure in “Extbase Yaml Routes” (routes)" url: "https://news.typo3.com/security/advisory/typo3-ext-sa-2021-008" description: It has been discovered that the extension “Extbase Yaml Routes” (routes) is susceptible to Sensitive Information Disclosure. 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-2021-008: Sensitive Information Disclosure in “Extbase Yaml Routes” (routes) - [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-2021-008: Sensitive Information Disclosure in “Extbase Yaml Routes” (routes) ========================================================================================= 10 August 2021 ![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 “Extbase Yaml Routes” (routes) is susceptible to Sensitive Information Disclosure. - ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/e4eaa13e33dd086a9c06f2570cb34609.jpeg)[Torben Hansen](https://news.typo3.com/article/author/torben-hansen) - Release Date: August 10, 2021 - Component Type: Third party extension. This extension is not a part of the TYPO3 default installation. - Component: “Extbase Yaml Routes” (routes) - Vulnerability Type: Sensitive Information Disclosure - Affected Versions: 2.1.0 and below - Severity: Medium - Suggested CVSS: [CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N/E:F/RL:O/RC:C](https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N/E:F/RL:O/RC:C&version=3.1) - References: [CVE-2021-36793](https://nvd.nist.gov/vuln/detail/CVE-2021-36793) ### Problem Description When using the CsrfTokenViewHelper the extension discloses the user's session identifier to HTML output without processing of additional cryptographic hashing algorithms. This vulnerability cannot be exploited directly and occurs in combination with a chained attack - like for instance Cross Site Scripting  in the frontend output. ### Solution An updated version 2.1.1 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 Security Team Member Oliver Hader for reporting the issue and to Serhii Borulko 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)