External Initialization of Trusted Variables or Data Stores Affecting getkirby/cms package, versions <4.9.4>=5.0.0-alpha.1, <5.4.4
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Test your applications- Snyk IDSNYK-PHP-GETKIRBYCMS-17423210
- published23 Jun 2026
- disclosed18 Jun 2026
- creditUnknown
Introduced: 18 Jun 2026
NewCVE-2026-54003 (opens in a new tab)How to fix?
Upgrade getkirby/cms to version 4.9.4, 5.4.4 or higher.
Overview
Affected versions of this package are vulnerable to External Initialization of Trusted Variables or Data Stores in the installation process when the Forwarded, X-Client-IP, or X-Real-IP headers are set by a reverse proxy. An attacker can gain unauthorized administrative access by remotely initiating the setup process and creating the first admin account. This is only exploitable if the site is running behind a reverse proxy that sets one of the affected headers and no admin account has been configured.
Workaround
This vulnerability can be mitigated by creating an initial admin account before exposing the site, or by disabling the REST API with the 'api' => false option in the configuration file.