CVE-2023-38492
MediumCVSS 5.3Exploitation Probability (EPSS)
Elevated risk59th percentile - higher than 59% of all known CVEs
Summary
A vulnerability in the Kirby content management system related to the lack of password length limitation in authentication endpoints was discovered. Attackers could provide a password up to the server's maximum request body length, potentially leading to CPU and memory resource exhaustion.
Risk Assessment
Although the real-world impact of this vulnerability is limited, it could cause the website to become unresponsive or unavailable. It is recommended to update to patched versions that also fix more severe vulnerabilities.
Recommendation
It is recommended to update to Kirby versions 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, or 3.9.6, which implement password length limits blocking passwords longer than 1000 bytes.
Other vulnerabilities in Kirby CMS
See all- CVE-2026-45368High
In Kirby CMS versions prior to 4.9.1 and 5.4.1, a vulnerability was found where URL methods for KirbyTags and image blocks components did not filter malicious URL values that resolve to script execution. Attackers can use URL formats like `javascript://x%0A…` to bypass protection against simple `javascript:` URLs and execute scripts.
- CVE-2026-45334Medium
In Kirby CMS versions prior to 4.9.1 and 5.4.1, the content-locking feature exposed user email addresses and identifiers without checking access permissions. A low-privilege authenticated user could learn the email and ID of any user currently editing a model, including administrators.
- CVE-2026-44177High
In Kirby CMS versions 5.3.0 through 5.4.0, a path traversal vulnerability was found due to improper validation of user IDs. An attacker could include arbitrary PHP files named index.php and probe the server's directory structure.
- CVE-2026-44176Medium
In Kirby CMS versions prior to 4.9.1 and 5.4.1, the `pages.access` permission was not checked during page draft rendering. An authenticated attacker with knowledge of the full path to an existing draft could access its frontend preview, leading to disclosure of sensitive information.
- CVE-2026-44175High
Kirby CMS versions prior to 4.9.1 and 5.4.1 do not properly sanitize the list field content on save, allowing XSS attacks. An attacker can bypass the Panel and send malicious HTML directly to the API, which will be executed in visitors' browsers.
- CVE-2026-44174High
Kirby CMS before versions 4.9.1 and 5.4.1 does not validate model attributes used in collection queries, allowing attackers to invoke arbitrary model methods. This can lead to disclosure of sensitive data (e.g., password hashes, filesystem paths) or execution of impactful actions (e.g., privilege escalation, mass deletion of models).
- CVE-2026-54004Medium
In Kirby CMS before versions 4.9.4 and 5.4.4, with content.fileRedirects enabled, unauthenticated clean file URL requests for files in top-level draft pages are redirected to physical media URLs without checking page access permissions or preview tokens, leading to disclosure of draft file contents.
- CVE-2026-54002High
A vulnerability in Kirby CMS before versions 4.9.4 and 5.4.4 allows stored cross-site scripting via malicious markup injected as children of unknown HTML/XML tags. The sanitization functions fail to properly filter such input.
- CVE-2026-50188Medium
A vulnerability in Kirby CMS allows HTTP header injection via newline characters in the header value of the headers option in the Http Remote class. An attacker can inject an unintended header into outgoing requests.
- CVE-2026-49276High
A vulnerability in the Kirby content management system allows a scripting link to be injected as the target of a link in the writer field, enabling self-cross-site scripting (XSS) in the Panel. The issue affects versions prior to 4.9.4 and 5.4.4.
Original NVD description (English source)
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 logins from each IP address and 10 failed logins for each existing user per hour. The problem has been patched in Kirby 3.5.8.3, 3.6.6.3, 3.7.5.2, 3.8.4.1, and 3.9.6. In all of the mentioned releases, the maintainers have added password length limits in the affected code so that passwords longer than 1000 bytes are immediately blocked, both when setting a password and when logging in.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

