TYPO3 is an open source PHP based web content management system released under the GNU GPL. It has been discovered that TYPO3 CMS is susceptible to host spoofing due to improper validation of the HTTP Host header. TYPO3 uses the HTTP Host header, for example, to generate absolute URLs during the frontend rendering process. Since the host header itself is provided by the client, it can be forged to any value, even in a name-based virtual hosts environment. This vulnerability is the same as described in TYPO3-CORE-SA-2014-001 (CVE-2014-3941). A regression, introduced during TYPO3 v11 development, led to this situation. The already existing setting $GLOBALS['TYPO3_CONF_VARS']['SYS']['trustedHostsPattern'] (used as an effective mitigation strategy in previous TYPO3 versions) was not evaluated anymore, and reintroduced the vulnerability.
History

Tue, 24 Feb 2026 18:15:00 +0000

Type Values Removed Values Added
Title HTTP Host Header Injection in Request Handling in Typo3 HTTP Host Header Injection in Request Handling in Typo3

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2021-10-05T17:15:11.000Z

Updated: 2024-08-04T02:59:31.581Z

Reserved: 2021-09-15T00:00:00.000Z

Link: CVE-2021-41114

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Modified

Published: 2021-10-05T18:15:08.293

Modified: 2024-11-21T06:25:29.837

Link: CVE-2021-41114

cve-icon Redhat

No data.