CVE-2021-21358

5.4 mediumEPSS 0.9%

Medium (5.4) in typo3 typo3. EPSS 0.9% chance of exploitation in the next 30 days.

TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 10.4.14, 11.1.1 it has been discovered that the Form Designer backend module of the Form Framework is vulnerable to cross-site scripting. A valid backend user account with access to the form module is needed to exploit this vulnerability. This is fixed in versions 10.4.14, 11.1.1.

Severity

CVSS 3.1

5.4 medium

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS: 0.9% chance of exploitation in the next 30 days; higher than 58% of CVEs (scores of 2026-11-01)
CWE: CWE-79
Published: 2021-03-23
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

typo3:typo3

References

https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-x79j-wgqv-g8h2
https://packagist.org/packages/typo3/cms-form
https://typo3.org/security/advisory/typo3-core-sa-2021-004
https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-x79j-wgqv-g8h2
https://packagist.org/packages/typo3/cms-form

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