CVE-2026-21896
January 08, 2026
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.
Affected Packages
https://github.com/getkirby/kirby.git (GITHUB):
Affected version(s) >=5.0.0 <5.2.2Fix Suggestion:
Update to version 5.2.2getkirby/cms (PHP):
Affected version(s) >=5.0.0 <5.2.2Fix Suggestion:
Update to version 5.2.2Related Resources (5)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.8
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
LOW
User Interaction
ACTIVE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
HIGH
Vulnerable System Availability
LOW
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
LOW
Weakness Type (CWE)
Incorrect Authorization
EPSS
Base Score:
0.03
