--- title: "TYPO3-CORE-SA-2020-011: Cleartext storage of session identifier" url: "https://news.typo3.com/security/advisory/typo3-core-sa-2020-011" description: It has been discovered that TYPO3 CMS is susceptible to sensitive data exposure. image: "https://news.typo3.com/_assets/d1e01514e4c4a5b3147940fa2ec50682/Images/og-image-news.jpg" date: 2026-06-11 modified: 2026-06-11 categories: - "Developer & Technology" - "Product Updates & Roadmap" - TYPO3 CMS --- # TYPO3-CORE-SA-2020-011: Cleartext storage of session identifier - [Developer & Technology](https://news.typo3.com/article/category/developer-technology) - [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-2020-011: Cleartext storage of session identifier =============================================================== 17 November 2020 ![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 susceptible to sensitive data exposure. - ![](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:** Session Storage (ext:core) - **Release Date:** November 17, 2020 - **Vulnerability Type:** Sensitive Data Exposure - **Affected Versions:** 10.0.0-10.4.9, 9.0.0-9.5.22, 8.7.0-8.7.37 ELTS, 7.6.0-7.6.47 ELTS, 6.2.0-6.2.53 ELTS - **Severity:** High - **Suggested CVSS:** [CVSS:3.1/AV:N/AC:H/PR:N/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:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C&version=3.1) - **References:** [CVE-2020-26228](https://nvd.nist.gov/vuln/detail/CVE-2020-26228), [CWE-312](https://cwe.mitre.org/data/definitions/312.html) ### Problem Description User session identifiers were stored in cleartext - without processing of additional cryptographic hashing algorithms. This vulnerability cannot be exploited directly and occurs in combination with a chained attack - like for instance SQL injection in any other component of the system. ### Solution Update to TYPO3 versions 10.4.10, 9.5.23, 8.7.38 ELTS, 7.6.48 ELTS or 6.2.54 ELTS that fix the problem described. ### Credits Thanks to TYPO3 security team member Helmut Hummel who reported this issue and to TYPO3 core & security team members Benni Mack & Oliver Hader as well as TYPO3 contributor Markus Klein 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)