CVE-2021-41114

HTTP Host Header Injection in Request Handling in Typo3

MEDIUM
5.3
CVSS Score
Published: October 5, 2021 at 05:15 PM UTC
Updated: June 17, 2026 at 04:07 AM UTC
1 product affected across 1 vendorTYPO3

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Severity
MEDIUM5.3
Exploit prediction
EPSS 1%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

95%
v < 11.5.011.0.0 ≤ v < 11.5.0
Affected range stops below 11.5.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-20CWE-644

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