What’s Vulnerable › Vulnerabilities

CVE-2021-21338: Open Redirection in Login Handling

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-03-23 · updated 2026-06-17
• Weakness: CWE-601

Description

TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 6.2.57, 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1 it has been discovered that Login Handling is susceptible to open redirection which allows attackers redirecting to arbitrary content, and conducting phishing attacks. No authentication is required in order to exploit this vulnerability. This is fixed in versions 6.2.57, 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1.

Affected products

• typo3: from 6.2.0 before 6.2.57; from 7.0.0 before 7.6.51; from 8.0.0 before 8.7.40; from 9.0.0 before 9.5.25; from 10.0.0 before 10.4.14; from 11.0.0 before 11.1.1 — fixed in 10.4.14, 11.1.1, 6.2.57, 7.6.51, 8.7.40, 9.5.25

How to fix

Upgrade to a fixed version: typo3 10.4.14, 11.1.1, 6.2.57, 7.6.51. Check the vendor advisory for mitigations.

References

• https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-4jhw-2p6j-5wmp
• https://packagist.org/packages/typo3/cms-core
• https://typo3.org/security/advisory/typo3-core-sa-2021-001
• https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-4jhw-2p6j-5wmp
• https://packagist.org/packages/typo3/cms-core
• https://typo3.org/security/advisory/typo3-core-sa-2021-001

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