Kirby CMS has pre-authentication path traversal and PHP file inclusion during user lookup

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.8 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-44177: 1.77% estimated exploitation activity in the next 30 days; percentile 78.17 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

TL;DR This vulnerability affects all Kirby sites on Kirby 5.3.0-5.4.0 and is independent from setup conditions and authentication. This vulnerability is of high severity for all Kirby sites. ---- Introduction Path traversal is a type of attack that allows to access arbitrary filesystem paths. By using special elements such as .. and / separators, attackers can escape outside of the restricted location to access files or directories that are elsewhere on the system. One of the most common special elements is the ../ sequence, which in most modern operating systems is interpreted as the parent directory of the current location. Path traversal can give attackers information about the filesystem and directory structure on the server and can lead to additional attacks depending on the nature of the accessible files and directories. PHP file inclusion is a type of attack that allows to load and execute PHP files on the server that are not intended for direct inclusion. Depending on the…

Published by the source

26 May 2026, 23:56 UTC

Last modified by the source

26 May 2026, 23:56 UTC

Source last checked

26 Oct 2026, 14:40 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9hx7-c53c-v6x8

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# Patch Next advisory brief: CVE-2026-44177

Advisory: Kirby CMS has pre-authentication path traversal and PHP file inclusion during user lookup
IDs: CVE-2026-44177, GHSA-9hx7-c53c-v6x8
Record: https://patchnext.com/advisories/cve-2026-44177 (revision 1, source checked 26 Oct 2026, 14:40 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: getkirby/cms 5.4.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist getkirby/cms: affected >= 5.3.0, <= 5.4.0; fixed in 5.4.1

## Suggested inspection (read-only)
- Packagist getkirby/cms: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on getkirby/cms.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-9hx7-c53c-v6x8 (GitHub-reviewed advisory GHSA-9hx7-c53c-v6x8 lists affected ranges: Packagist getkirby/cms >=5.3.0 <=5.4.0)

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