CVE-2026-54002

Kirby: Cross-site scripting (XSS) from incomplete HTML/XML sanitization in `Dom::sanitize()`

HIGH
8.5
CVSS Score
Published: July 9, 2026 at 06:34 PM UTC
Updated: October 25, 2026 at 05:10 PM UTC
1 product affected across 1 vendorKirby

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Severity
HIGH8.5
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites and plugins that use the writer or list fields or call Dom::sanitize(), Sane::sanitize(), Sane::Html::sanitize(), Sane::Svg::sanitize(), Sane::Xml::sanitize(), Sane::sanitizeFile(), or file sanitizeContents() with untrusted input allow malicious markup injected as children of an unknown HTML or XML tag to pass through Dom::sanitize() without being correctly sanitized, causing stored cross-site scripting. This issue is fixed in versions 4.9.4 and 5.4.4.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

90%
Affected range stops below 4.9.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 5.4.4, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.5HIGHGitHub_M
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-79CWE-87

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