vulnerability / NVI-00001823 / Revision 3
HTTP Host Header Injection
OSV carries this publisher advisory for typo3/cms-core, typo3/cms. This is an aggregated source copy; consult the original publisher and compare update dates.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
1.221%
FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.68744. Missing scores are unknown.
As of · FIRST EPSS
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
typo3/cms-core
source listedECOSYSTEM: introduced 11.0.0; fixed 11.5.0
### Meta * CVSS: `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:F/RL:O/RC:C` (3.5) ### Problem 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 _$GLOBALS['TYPO3_CONF_VARS']['SYS']['trustedHostsPattern']_ (used as an effective mitigation strategy in previous TYPO3 versions) was not evaluated anymore, and reintroduced the vulnerability. ### Solution Update your instance to TYPO3 version 11.5.0 which addresses the problem described. ### Credits Thanks to TYPO3 framework merger Benjamin Franzke who reported and fixed the issue. ### References * [TYPO3-CORE-SA-2021-015](https://typo3.org/security/advisory/typo3-
typo3/cms
source listedECOSYSTEM: introduced 11.0.0; fixed 11.5.0
### Meta * CVSS: `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:F/RL:O/RC:C` (3.5) ### Problem It has been discovered that TYPO3 CMS is susceptible to host spoofing due to improper validation of the HTTP _Host_ header. TYPO3 uses the HTTP _Host_ header, for example, to generate absolute URLs during the frontend rendering process. Since the host header itself is provided by the client, it can be forged to any value, even in a name-based virtual hosts environment. This vulnerability is the same as described in TYPO3-CORE-SA-2014-001 (CVE-2014-3941). A regression, introduced during TYPO3 v11 development, led to this situation. The already existing setting _$GLOBALS['TYPO3_CONF_VARS']['SYS']['trustedHostsPattern']_ (used as an effective mitigation strategy in previous TYPO3 versions) was not evaluated anymore, and reintroduced the vulnerability. ### Solution Update your instance to TYPO3 version 11.5.0 which addresses the problem described. ### Credits Thanks to TYPO3 framework merger Benjamin Franzke who reported and fixed the issue. ### References * [TYPO3-CORE-SA-2021-015](https://typo3.org/security/advisory/typo3-
03 / Response
What to do next
- vendor patch
The original advisory lists fixed boundaries 11.5.0 for typo3/cms-core. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
- vendor patch
The original advisory lists fixed boundaries 11.5.0 for typo3/cms. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. FIRST EPSS
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-m2jh-fxw4-gphm ↗
GitHub Advisory Database via OSV · vendor advisory
Observed . GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.
- CVE-2021-41114 ↗
FIRST EPSS · official catalog
Observed . FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 3 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 2 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.