Kirby is a content management system. A vulnerability in versions prior to 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6 only affects Kirby sites that use the `Xml` data handler (e.g. `Data::decode($string, 'xml')`) or the `Xml::parse()` method in site or plugin code. The Kirby core does not use any of the affected methods. XML External Entities (XXE) is a little used feature in the XML markup language that allows to include data from external files in an XML structure. If the name of the external file can be controlled by an attacker, this becomes a vulnerability that can be abused for various system impacts like the disclosure of internal or confidential data that is stored on the server (arbitrary file disclosure) or to perform network requests on behalf of the server (server-side request forgery, SSRF). Kirby's `Xml::parse()` method used PHP's `LIBXML_NOENT` constant, which enabled the processing of XML external entities during the parsing operation. The `Xml::parse()` method is…

Kirby is a CMS targeting designers and editors. Kirby allows to restrict the permissions of specific user roles. Users of that role can only perform permitted actions. Permissions for creating and deleting languages have already existed and could be configured, but were not enforced by Kirby's frontend or backend code. A permission for updating existing languages has not existed before the patched versions. So disabling the languages.* wildcard permission for a role could not have prohibited updates to existing language definitions. The missing permission checks allowed attackers with Panel access to manipulate the language definitions. The problem has been patched in Kirby 3.6.6.6, Kirby 3.7.5.5, Kirby 3.8.4.4, Kirby 3.9.8.2, Kirby 3.10.1.1, and Kirby 4.3.1. Please update to one of these or a later version to fix the vulnerability. There are no known workarounds for this vulnerability.

Kirby is a content management system. The new link field introduced in Kirby 4 allows several different link types that each validate the entered link to the relevant URL format. It also includes a "Custom" link type for advanced use cases that don't fit any of the pre-defined link formats. As the "Custom" link type is meant to be flexible, it also allows the javascript: URL scheme. In some use cases this can be intended, but it can also be misused by attackers to execute arbitrary JavaScript code when a user or visitor clicks on a link that is generated from the contents of the link field. This vulnerability is patched in 4.1.1.

Kirby is a content management system. A vulnerability in versions prior to 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6 affects all Kirby sites with user accounts (unless Kirby's API and Panel are disabled in the config). The real-world impact of this vulnerability is limited, however we still recommend to update to one of the patch releases because they also fix more severe vulnerabilities. Kirby's authentication endpoint did not limit the password length. This allowed attackers to provide a password with a length up to the server's maximum request body length. Validating that password against the user's actual password requires hashing the provided password, which requires more CPU and memory resources (and therefore processing time) the longer the provided password gets. This could be abused by an attacker to cause the website to become unresponsive or unavailable. Because Kirby comes with a built-in brute force protection, the impact of this vulnerability is limited to 10 failed…

Kirby is a content management system. A vulnerability in versions prior to 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6 affects all Kirby sites that might have potential attackers in the group of authenticated Panel users or that allow external visitors to upload an arbitrary file to the content folder. Kirby sites are not affected if they don't allow file uploads for untrusted users or visitors or if the file extensions of uploaded files are limited to a fixed safe list. The attack requires user interaction by another user or visitor and cannot be automated. An editor with write access to the Kirby Panel could upload a file with an unknown file extension like `.xyz` that contains HTML code including harmful content like `<script>` tags. The direct link to that file could be sent to other users or visitors of the site. If the victim opened that link in a browser where they are logged in to Kirby and the file had not been opened by anyone since the upload, Kirby would not be able to …

Kirby is a content management system. A vulnerability in versions prior to 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6 affects all Kirby sites with user accounts (unless Kirby's API and Panel are disabled in the config). It can only be abused if a Kirby user is logged in on a device or browser that is shared with potentially untrusted users or if an attacker already maliciously used a previous password to log in to a Kirby site as the affected user. Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization. In the variation described in this advisory, it allows attackers to stay logged in to a Kirby site on another device even if the logged in user has since changed their password. Kirby did not invalidate user sessions that were created with a password that was since changed by the user or by a site admin. If a user changed their password to lock out an attacker who was already in possession of the prev…

Kirby is a content management system. A vulnerability in versions prior to 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6 affects all Kirby sites that might have potential attackers in the group of authenticated Panel users or that allow external visitors to update a Kirby content file (e.g. via a contact or comment form). Kirby sites are *not* affected if they don't allow write access for untrusted users or visitors. A field injection in a content storage implementation is a type of vulnerability that allows attackers with content write access to overwrite content fields that the site developer didn't intend to be modified. In a Kirby site this can be used to alter site content, break site behavior or inject malicious data or code. The exact security risk depends on the field type and usage. Kirby stores content of the site, of pages, files and users in text files by default. The text files use Kirby's KirbyData format where each field is separated by newlines and a line with four d…

Kirby is a Content Management System. Prior to versions 3.5.8.2, 3.6.6.2, 3.7.5.1, and 3.8.1, a user enumeration vulnerability affects all Kirby sites with user accounts unless Kirby's API and Panel are disabled in the config. It can only be exploited for targeted attacks because the attack does not scale to brute force. The problem has been patched in Kirby 3.5.8.2, Kirby 3.6.6.2, Kirby 3.7.5.1, and Kirby 3.8.1. In all of the mentioned releases, the maintainers have rewritten the affected code so that the delay is also inserted after the brute force limit is reached.

Kirby is a flat-file CMS. In versions prior to 3.5.8.2, 3.6.6.2, 3.7.5.1, and 3.8.1, Kirby is subject to user enumeration due to Improper Restriction of Excessive Authentication Attempts. This vulnerability affects you only if you are using the `code` or `password-reset` auth method with the `auth.methods` option or if you have enabled the `debug` option in production. By using two or more IP addresses and multiple login attempts, valid user accounts will lock, but invalid accounts will not, leading to account enumeration. This issue has been patched in versions 3.5.8.2, 3.6.6.2, 3.7.5.1, and 3.8.1. If you cannot update immediately, you can work around the issue by setting the `auth.methods` option to `password`, which disables the code-based login and password reset forms.

kirby is a content management system (CMS) that adapts to many different projects and helps you build your own ideal interface. Cross-site scripting (XSS) is a type of vulnerability that allows execution of any kind of JavaScript code inside the Panel session of the same or other users. In the Panel, a harmful script can for example trigger requests to Kirby's API with the permissions of the victim. If bad actors gain access to your group of authenticated Panel users they can escalate their privileges via the Panel session of an admin user. Depending on your site, other JavaScript-powered attacks are possible. The multiselect field allows selection of tags from an autocompleted list. Unfortunately, the Panel in Kirby 3.5 used HTML rendering for the raw option value. This allowed **attackers with influence on the options source** to store HTML code. The browser of the victim who visited a page with manipulated multiselect options in the Panel will then have rendered this malicious HTML…