VulnerabilityAnalyzed

CVE-2026-21896

From versions 5.0.0 to 5.2.1, Kirby is missing permission checks in the content changes API.

MEDIUM 5.8EPSS 0.22%

Does this matter?

Lower severity and a low EPSS score (0.22%). Track it; it rarely justifies an emergency change on its own.

Description

Kirby is an open-source content management system. From versions 5.0.0 to 5.2.1, Kirby is missing permission checks in the content changes API. This vulnerability affects all Kirby sites where user permissions are configured to prevent specific role(s) from performing write actions, specifically by disabling the update permission with the intent to prevent modifications to site content. This vulnerability does not affect those who have not altered the deviated from default user permissions. This issue has been patched in version 5.2.2.

CVSS 4.0: 5.8 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.22% probability · 13th percentile
CISA KEV: Not listed
Weakness: CWE-863
Affected: getkirby/kirby
Source: security-advisories@github.com

References

https://github.com/getkirby/kirby/commit/f5ce1347b427b819bf193acf11fd0da232f7af47Patch
https://github.com/getkirby/kirby/releases/tag/5.2.2Product, Release Notes
https://github.com/getkirby/kirby/security/advisories/GHSA-4j78-4xrm-cr2fPatch, Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.