CVE-2020-26255: PHP Phar archives could be uploaded and executed in Kirby

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-12-08 · updated 2026-06-17
Weakness: CWE-434

Description

Kirby is a CMS. In Kirby CMS (getkirby/cms) before version 3.4.5, and Kirby Panel before version 2.5.14 , an editor with full access to the Kirby Panel can upload a PHP .phar file and execute it on the server. This vulnerability is critical if you might have potential attackers in your group of authenticated Panel users, as they can gain access to the server with such a Phar file. Visitors without Panel access *cannot* use this attack vector. The problem has been patched in Kirby 2.5.14 and Kirby 3.4.5. Please update to one of these or a later version to fix the vulnerability. Note: Kirby 2 reaches end of life on December 31, 2020. We therefore recommend to upgrade your Kirby 2 sites to Kirby 3. If you cannot upgrade, we still recommend to update to Kirby 2.5.14.

Affected products

getkirby kirby: before 3.4.5 — fixed in 3.4.5
getkirby Panel: before 2.5.14 — fixed in 2.5.14

How to fix

Upgrade to a fixed version: getkirby kirby 3.4.5; getkirby Panel 2.5.14. Check the vendor advisory for mitigations.

References

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