--- title: "TYPO3-CORE-SA-2016-017: Information Disclosure in TYPO3 Backend" url: "https://news.typo3.com/security/advisory/typo3-core-sa-2016-017" description: It has been discovered, that TYPO3 is susceptible to Information Disclosure. image: "https://news.typo3.com/_assets/d1e01514e4c4a5b3147940fa2ec50682/Images/og-image-news.jpg" date: 2026-06-11 modified: 2026-06-11 categories: - "Product Updates & Roadmap" - TYPO3 CMS --- # TYPO3-CORE-SA-2016-017: Information Disclosure in TYPO3 Backend - [Product Updates & Roadmap](https://news.typo3.com/article/category/product-updates-roadmap) - Security / [TYPO3 CMS](https://news.typo3.com/article/category/security/typo3-cms) TYPO3-CORE-SA-2016-017: Information Disclosure in TYPO3 Backend =============================================================== 19 July 2016 ![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 TYPO3 is susceptible to Information Disclosure. - ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/bbf959d8e683550c90ae922aff9145d8.jpeg)[Marcus Krause](https://news.typo3.com/article/author/marcus-krause) **Component Type:** TYPO3 CMS **Release Date:** July 19, 2016 Vulnerable subcomponent: Backend -------------------------------- **Vulnerability Type:** Information Disclosure **Affected Versions:** Versions 6.2.0 to 6.2.25, 7.6.0 to 7.6.9 and 8.0.0 to 8.2.0 **Severity:** Low **Suggested CVSS v2.0:** [AV:N/AC:M/Au:N/C:P/I:N/A:N/E:P/RL:O/RC:C](http://jvnrss.ise.chuo-u.ac.jp/jtg/cvss/cvss2.cgi?vector=%28AV:N/AC:M/Au:N/C:P/I:N/A:N/E:P/RL:O/RC:C%29&g=2&lang=en) **CVE:** not assigned yet **Problem Description:** The TYPO3 backend module stores the username of an authenticated backend user in its cache files. By guessing the file path to the cache files it is possible to receive valid backend usernames. **Solution:** Update to TYPO3 versions 6.2.26, 7.6.10 or 8.2.1 that fix the problem described. **Credits:** Thanks to Matthias Kappenberg who discovered and reported the issue. **General Advice:** Follow the recommendations that are given in the [TYPO3 Security Guide](http://docs.typo3.org/typo3cms/SecurityGuide/ "Opens external link in new window"). Please subscribe to the [typo3-announce](http://lists.typo3.org/cgi-bin/mailman/listinfo/typo3-announce) mailing list. **General Note:** All security related code changes are tagged so that you can easily look them up on our [review system](https://review.typo3.org/#/q/status:merged+project:Packages/TYPO3.CMS+topic:security,n,z). ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/b5c88386e5b1d8fca79d0652427922d2.jpeg) About the Author [Marcus Krause](https://news.typo3.com/article/author/marcus-krause) [More posts by this author](https://news.typo3.com/article/author/marcus-krause)