Summary
Problem
Backend users with file write permissions were able to upload form definition files with mixed-case extensions (e.g., .FORM.YAML) to bypass the Form Framework's upload restriction. Maliciously crafted form definition files can be used to execute arbitrary SQL statements, allowing attackers to escalate privileges by creating administrative backend user accounts.
Credits
TYPO3 CMS thanks Alexander Künzl for reporting this issue, and to TYPO3 core & security team members Oliver Hader and Benjamin Franzke for fixing it.
Resources
Impact
The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Update to TYPO3 versions 10.4.57 ELTS, 11.5.51 ELTS, 12.4.46 ELTS, 13.4.31 LTS, 14.3.3 LTS that fix the problem described.
Frequently Asked Questions
- What is CVE-2026-47346? CVE-2026-47346 is a high-severity missing authorization vulnerability in typo3/cms-core (composer), affecting versions < 10.4.57. It is fixed in 10.4.57, 11.5.51, 12.4.46, 13.4.31, 14.3.3. The application does not perform an authorization check before performing a sensitive operation.
- Which packages are affected by CVE-2026-47346?
typo3/cms-core(composer) (versions < 10.4.57)typo3/cms-form(composer) (versions < 10.4.57)
- Is there a fix for CVE-2026-47346? Yes. CVE-2026-47346 is fixed in 10.4.57, 11.5.51, 12.4.46, 13.4.31, 14.3.3. Upgrade to this version or later.
- Is CVE-2026-47346 exploitable, and should I be worried? Whether CVE-2026-47346 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-47346 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-47346?
- Upgrade
typo3/cms-coreto 10.4.57 or later - Upgrade
typo3/cms-coreto 11.5.51 or later - Upgrade
typo3/cms-coreto 12.4.46 or later - Upgrade
typo3/cms-coreto 13.4.31 or later - Upgrade
typo3/cms-coreto 14.3.3 or later - Upgrade
typo3/cms-formto 10.4.57 or later - Upgrade
typo3/cms-formto 11.5.51 or later - Upgrade
typo3/cms-formto 12.4.46 or later - Upgrade
typo3/cms-formto 13.4.31 or later - Upgrade
typo3/cms-formto 14.3.3 or later
- Upgrade