Summary
Kirby CMS's read access to site, user and role information is not gated by permissions
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.
Sites using Kirby are not affected if they intend all users of the site to be able to list and access the site model and all users and roles, including the content stored within these models. Write actions are not affected by this vulnerability as they were gated by permissions before.
Introduction
Missing authorization allows authenticated users to perform actions they are not intended to have access to.
The effects of missing authorization can include unauthorized access to sensitive information as well as unauthorized changes to content or system information.
Credits
Kirby thanks @HuajiHD for responsibly reporting the identified issue.
Impact
Kirby's user permissions control which user role is allowed to perform specific actions to content models in the CMS. These permissions are defined for each role in the user blueprint (site/blueprints/users/...). It is also possible to customize the permissions for each target model in the model blueprints (such as in site/blueprints/pages/...) using the options feature. The permissions and options together control the authorization of user actions.
In affected releases, Kirby did not provide permission settings that control the access to the site model as well as to users and user roles. If the site developer disabled all permissions via the wildcard "*": false setting, this only disabled the actions that were explicitly gated by existing permissions.
To be specific, the following permissions were missing in affected releases and have been added in the patches:
site.accessuser.accessandusers.access(for the own user and other users respectively)user.listandusers.list(for the own user and other users respectively)
Access to role information such as the list of existing roles, their names and descriptions as well as their configured permissions were also not gated by user-based permissions.
The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.
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 4.9.0 and Kirby 5.4.0. Please update to one of these or a later version to fix the vulnerability.
In all of the mentioned releases, Kirby has added the missing permissions that are listed in the "Impact" section. The user.access and users.access permissions also take effect on the access to the user's own role and to other roles respectively.
Frequently Asked Questions
- What is CVE-2026-42069? CVE-2026-42069 is a high-severity missing authorization vulnerability in getkirby/cms (composer), affecting versions <= 4.8.0. It is fixed in 4.9.0, 5.4.0. The application does not perform an authorization check before performing a sensitive operation.
- Which versions of getkirby/cms are affected by CVE-2026-42069? getkirby/cms (composer) versions <= 4.8.0 is affected.
- Is there a fix for CVE-2026-42069? Yes. CVE-2026-42069 is fixed in 4.9.0, 5.4.0. Upgrade to this version or later.
- Is CVE-2026-42069 exploitable, and should I be worried? Whether CVE-2026-42069 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-2026-42069 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-2026-42069?
- Upgrade
getkirby/cmsto 4.9.0 or later - Upgrade
getkirby/cmsto 5.4.0 or later
- Upgrade