--- title: "TYPO3-CORE-SA-2017-007: Arbitrary Code Execution in TYPO3 CMS" url: "https://news.typo3.com/security/advisory/typo3-core-sa-2017-007" description: It has been discovered, that TYPO3 CMS is vulnerable to Arbitrary Code Execution. image: "https://news.typo3.com/_assets/d1e01514e4c4a5b3147940fa2ec50682/Images/og-image-news.jpg" date: 2026-06-11 modified: 2026-06-11 categories: - "Developer & Technology" - TYPO3 CMS --- # TYPO3-CORE-SA-2017-007: Arbitrary Code Execution in TYPO3 CMS - [Developer & Technology](https://news.typo3.com/article/category/developer-technology) - Security / [TYPO3 CMS](https://news.typo3.com/article/category/security/typo3-cms) TYPO3-CORE-SA-2017-007: Arbitrary Code Execution in TYPO3 CMS ============================================================= 05 September 2017 ![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 CMS is vulnerable to Arbitrary Code Execution. - ![](https://news.typo3.com/typo3temp/assets/t3g/blog/gravatar/b8266fdc667b773926c59081862ab148.jpeg)[Oliver Hader](https://news.typo3.com/article/author/oliver-hader) **Component Type:** TYPO3 CMS **Release Date:** September 5, 2017 **Vulnerability Type:** Arbitrary Code Execution **Affected Versions:** 7.6.0 to 7.6.21 and 8.0.0 to 8.7.4 **Severity:** None - High (depending on web server configuration) **Suggested CVSS v2.0:** [AV:N/AC:L/Au:S/C:C/I:C/A:C/E:F/RL:OF/RC:C](https://nvd.nist.gov/vuln-metrics/cvss/v2-calculator?vector=(AV:N/AC:L/Au:S/C:C/I:C/A:C/E:F/RL:OF/RC:C)) **CVE:** not assigned yet **Problem Description:** Due to a missing file extension in the fileDenyPattern, backend user are allowed to upload \*.pht files which can be executed in certain web server setups. The new default fileDenyPattern is the following, which might have been overridden in the TYPO3 Install Tool. ``` \.(php[3-7]?|phpsh|phtml|pht)(\..*)?$|^\.htaccess$ ``` **Solution:** Update to TYPO3 versions 7.6.22 or 8.7.5 that fix the problem described, make sure overridden settings for *TYPO3\_CONF\_VARS/BE/fileDenyPattern* are adjusted. **Credits:** Thanks to Maurizio Siddu who reported this issue and to TYPO3 core team member Susanne Moog who fixed 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/cc7cba9757f98fbe05023a139119df74.jpeg) About the Author [Oliver Hader](https://news.typo3.com/article/author/oliver-hader) Core Developer at TYPO3 GmbH,Hof, Germany [Website](https://typo3.com)[Twitter](https://twitter.com/ohader)[LinkedIn](https://www.linkedin.com/in/oliverhader/)[Xing](https://www.xing.com/profile/Oliver_Hader) Oliver started to work with TYPO3 in 2005 and was fascinated by the product and its universe. Since 2007 he is member of the TYPO3 Core Team. After going back to university in 2014 for achieving a postgraduate master degree in internet web science, he is now researching on advanced web technology topics in general and for TYPO3 in particular. In his spare time, Oliver loves to go cycling cross-country in the uplands around Hof (Germany) in northern Bavaria - at the region where he's living as well. [More posts by this author](https://news.typo3.com/article/author/oliver-hader)