CVE-2024-27087: Kirby cross-site scripting (XSS) in the link field "Custom" type

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-02-26 · updated 2026-06-17
Weakness: CWE-79

Description

Kirby is a content management system. The new link field introduced in Kirby 4 allows several different link types that each validate the entered link to the relevant URL format. It also includes a "Custom" link type for advanced use cases that don't fit any of the pre-defined link formats. As the "Custom" link type is meant to be flexible, it also allows the javascript: URL scheme. In some use cases this can be intended, but it can also be misused by attackers to execute arbitrary JavaScript code when a user or visitor clicks on a link that is generated from the contents of the link field. This vulnerability is patched in 4.1.1.

Affected products

getkirby kirby: from 4.0.0 before 4.1.1 — fixed in 4.1.1

How to fix

Upgrade to a fixed version: getkirby kirby 4.1.1. Check the vendor advisory for mitigations.

References

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