--- title: "TYPO3-EXT-SA-2016-021: Denial of Service in extension \"Speaking URLs for TYPO3\" (realurl)" url: "https://news.typo3.com/security/advisory/typo3-ext-sa-2016-021" description: "It has been discovered that the extension \"Speaking URLs for TYPO3\" (realurl) is susceptible to Denial of Service." image: "https://news.typo3.com/_assets/d1e01514e4c4a5b3147940fa2ec50682/Images/og-image-news.jpg" date: 2026-06-11 modified: 2026-06-11 categories: - TYPO3 Extensions --- # TYPO3-EXT-SA-2016-021: Denial of Service in extension "Speaking URLs for TYPO3" (realurl) - Security / [TYPO3 Extensions](https://news.typo3.com/article/category/security/typo3-extensions) TYPO3-EXT-SA-2016-021: Denial of Service in extension "Speaking URLs for TYPO3" (realurl) ========================================================================================= 08 September 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 the extension "Speaking URLs for TYPO3" (realurl) is susceptible to Denial of Service. - ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/7569d41262328e5ed8d27b53e03970ec.png)[Helmut Hummel](https://news.typo3.com/article/author/helmut-hummel) **Release Date:** September 8, 2016 **Component Type:** Third party extension. This extension is not a part of the TYPO3 default installation. **Affected Versions:** version 2.0.0 to 2.0.14 **Vulnerability Type:** Denial of Service **Severity:** Medium **Suggested CVSS v2.0:** [AV:N/AC:L/Au:N/C:N/I:N/A:C/E:F/RL:O/RC:C](http://jvnrss.ise.chuo-u.ac.jp/jtg/cvss/cvss2.cgi?vector=%28AV:N/AC:L/Au:N/C:N/I:N/A:C/E:F/RL:O/RC:C%29&g=2&lang=en "CVSS calculator") ([What's that?](http://buzz.typo3.org/teams/security/article/use-of-common-vulnerability-scoring-system-in-typo3-security-advisories/ "Blog post on CVSS usage")) **Problem Description:** The extension allows an attacker to forge URLs with arbitrary cHash values by regenerating the cHash GET argument. This results in the possibility to create an arbitrary amount of page cache entries. Exceeding database storage limits will eventually lead to the TYPO3 page not responding any more. **Solution:** An updated version 2.0.15 is available from the TYPO3 Extension Manager and at [https://typo3.org/extensions/repository/download/realurl/2.0.15/t3x/](https://typo3.org/extensions/repository/download/realurl/2.0.15/t3x/ "Opens external link in new window"). Users of the extension are advised to update the extension as soon as possible. **Credits:** Thanks to Robert Vock and Timo Pfeffer 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/ "Initiates file download"). Please subscribe to the [typo3-announce mailing list](http://lists.typo3.org/cgi-bin/mailman/listinfo/typo3-announce "Opens external link in new window") to receive future Security Bulletins via E-mail. ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/bb9efc51bced8582e7b8c235f4b5f2b5.png) About the Author [Helmut Hummel](https://news.typo3.com/article/author/helmut-hummel) [More posts by this author](https://news.typo3.com/article/author/helmut-hummel)