Summary
Kirby CMS has an Arbitrary Method Call via REST API Search and Collection Query Endpoints
TL;DR
This vulnerability affects all Kirby sites that might have potential attackers in the group of authenticated Panel users.
This vulnerability is of high severity for affected sites and has a high real-world impact.
Introduction
Arbitrary method call is a type of arbitrary code execution. It is a vulnerability that allows attackers to run any commands or code of the attacker's choice on a target machine or in a target process.
Depending on the set of accessible methods, this can lead to disclosure of sensitive information or to unintended and malicious write actions.
Affected components
Kirby's data model is made up of model objects that are contained in collection objects. These collections can be queried with methods such as $collection->filter(), $collection->sort(), $collection->group(), $collection->pluck() and $collection->findBy(). Each of these methods allows to query the models contained in the collection by any accessible model attribute (field or method).
Kirby also provides endpoints in its REST API that allow to search through users or through children and files of the site or of a particular page. These endpoints allow the search, not, filter and sort queries as well as options to paginate the result. The same kind of queries can also be provided to API collections such as /<site|page|user>/blueprints, /<site|page>/children, /<model>/files, /languages, /roles, /translations, /users and /<user>/roles.
Credits
Kirby thanks @mojamojam for responsibly reporting the identified issue.
Impact
In affected releases, Kirby did not validate the model attributes that were used in the collection queries. This allowed attackers to include arbitrary model methods in their queries. This includes methods with sensitive data such as password() (disclosing the password hash) or root() (disclosing the absolute filesystem path on the server) as well as methods that perform impactful actions such as loginPasswordless() (causing a privilege escalation to another user) or delete() (deleting all queried models in one go if the authenticated user has appropriate permissions).
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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The problem has been patched in Kirby 4.9.1 and Kirby 5.4.1. Please update to one of these or a later version to fix the vulnerability.
In all of the mentioned releases, Kirby has added a blocklist of sensitive model methods that should not be called during collection operations and limited the query options for the affected endpoints to search and pagination.
Frequently Asked Questions
- What is CVE-2026-44174? CVE-2026-44174 is a high-severity security vulnerability in getkirby/cms (composer), affecting versions <= 4.9.0. It is fixed in 4.9.1, 5.4.1.
- Which versions of getkirby/cms are affected by CVE-2026-44174? getkirby/cms (composer) versions <= 4.9.0 is affected.
- Is there a fix for CVE-2026-44174? Yes. CVE-2026-44174 is fixed in 4.9.1, 5.4.1. Upgrade to this version or later.
- Is CVE-2026-44174 exploitable, and should I be worried? Whether CVE-2026-44174 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-44174 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-44174?
- Upgrade
getkirby/cmsto 4.9.1 or later - Upgrade
getkirby/cmsto 5.4.1 or later
- Upgrade