CVE-2026-47346: TYPO3 CMS privilege escalation in Form Framework via mixed-case extensions

CVE-2026-47346 · Severity: high · CVSS 4 · Published 2026-06-09

TYPO3 CMS, a popular web content management system, contains a security flaw in its form-building component. An authorized user with basic file upload permissions can bypass security restrictions to upload malicious configuration files. This allows an attacker to execute unauthorized database commands and create new administrator accounts, potentially leading to a full takeover of the website.

Technologies: typo3/cms-core (Packagist), typo3/cms-form (Packagist). Vendors: Packagist.

Quick answers

Is CVE-2026-47346 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-47346 being exploited in the wild.
How severe is CVE-2026-47346?
High severity, with a CVSS score of 4, published 9 June 2026.
Which products and versions are affected?
typo3/cms-core (Packagist) ECOSYSTEM:introduced=0,fixed=10.4.57; typo3/cms-form (Packagist) ECOSYSTEM:introduced=0,fixed=10.4.57.
Is there a fix for CVE-2026-47346?
Yes. typo3/cms-core (Packagist): upgrade to 10.4.57 or later; typo3/cms-form (Packagist): upgrade to 10.4.57 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-47346 attacked?
It is attacked over the network, in a web application.
Am I affected by CVE-2026-47346?
Check whether you run typo3/cms-core (Packagist) or typo3/cms-form (Packagist) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • typo3/cms-core (Packagist): upgrade to 10.4.57 or later
    composer require typo3/cms-core:^10.4.57
  • typo3/cms-form (Packagist): upgrade to 10.4.57 or later
    composer require typo3/cms-form:^10.4.57

Technical details

A broken access control vulnerability exists in the TYPO3 Form Framework due to improper handling of case sensitivity (CWE-178) during file extension validation. Backend users with existing file write permissions can bypass upload restrictions by using mixed-case extensions (e.g., '.FORM.YAML') for form definition files. Once uploaded, these maliciously crafted YAML files can be processed to execute arbitrary SQL statements. This enables an attacker to perform privilege escalation, such as creating new administrative backend accounts. The vulnerability is patched in versions 10.4.57 ELTS, 11.5.51 ELTS, 12.4.46 ELTS, 13.4.31 LTS, and 14.3.3 LTS.

Affected products

  • TYPO3 TYPO3 CMS < 10.4.57, 11.0.0-11.5.50, 12.0.0-12.4.45, 13.0.0-13.4.30, 14.0.0-14.3.2

Identifiers

  • CVE-2026-47346
  • GHSA-hwvq-2w67-rvxp

Timeline

  • 2026-06-09: disclosed
  • 2026-06-09: patched
  • 2026-06-12: advisory

References

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