--- title: "TYPO3-CORE-SA-2019-026: Insecure Deserialization in Query Generator & Query View" url: "https://news.typo3.com/security/advisory/typo3-core-sa-2019-026" description: It has been discovered that TYPO3 CMS is vulnerable to insecure deserialization. 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-2019-026: Insecure Deserialization in Query Generator & Query View - [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-2019-026: Insecure Deserialization in Query Generator & Query View ==================================================================================== 17 December 2019 ![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 insecure deserialization. - ![](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 - **Subcomponent:** Query Generator & Query View (ext:lowlevel, ext:core) - **Release Date:** December 17, 2019 - **Vulnerability Type:** Insecure Deserialization - **Affected Versions:** 8.0.0-8.7.29 and 9.0.0-9.5.11 and 10.0.0-10.2.0 - **Severity:** Medium - High - **Suggested CVSS v3.1:** [AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C](https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C&version=3.1) - **CVE:** [CVE-2019-19849](https://nvd.nist.gov/vuln/detail/CVE-2019-19849) ### Problem Description It has been discovered that classes *QueryGenerator* and *QueryView* are vulnerable to insecure deserialization. Requirements for successfully exploiting this vulnerability (one of the following): - having system extension *ext:lowlevel* (Backend Module: DB Check) installed & valid backend user having administrator privileges - having system extension *ext:sys\_action* installed & valid backend user having limited privileges ### Solution Update to TYPO3 versions 8.7.30 or 9.5.12 or 10.2.2 that fix the problem described. ### Credits Thanks to Daniel Windloff who reported this issue and to TYPO3 framework merger Frank Nägler who fixed the issue. ### General Advice Follow the recommendations that are given in the [TYPO3 Security Guide](https://docs.typo3.org/typo3cms/CoreApiReference/Security/Index.html#security). 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 in 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)