How severe is GHSA-9wfj-c55w-j9qr?

No CVSS score has been assigned to GHSA-9wfj-c55w-j9qr yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-9wfj-c55w-j9qr?

GHSA-9wfj-c55w-j9qr affects the following packages: getkirby/cms (Packagist), getkirby/cms (Packagist). Ecosystems affected: Packagist.

How do I fix GHSA-9wfj-c55w-j9qr?

Update getkirby/cms to 4.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9wfj-c55w-j9qr is resolved across your whole dependency graph.

How do I detect GHSA-9wfj-c55w-j9qr in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getkirby/cms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-9wfj-c55w-j9qr if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-9wfj-c55w-j9qr?

O3 pinpoints whether GHSA-9wfj-c55w-j9qr is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-9wfj-c55w-j9qr actively exploited in the wild?

No public exploit code has been indexed for GHSA-9wfj-c55w-j9qr yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What type of vulnerability is GHSA-9wfj-c55w-j9qr?

GHSA-9wfj-c55w-j9qr is classified as CWE-91 (CWE-91). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-9wfj-c55w-j9qr published, and has it been updated?

GHSA-9wfj-c55w-j9qr was published on April 23, 2026 and was last updated on May 5, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐘 Packagist

Not in CISA KEV

GHSA-9wfj-c55w-j9qr

GHSA-9wfj-c55w-j9qr is a CWE-91 vulnerability in getkirby/cms. O3 Security confirms whether GHSA-9wfj-c55w-j9qr is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Kirby has XML injection in its XML creator toolkit

Also known asCVE-2026-32870

Published

Apr 23, 2026

Updated

May 5, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of May 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Real-World Exposure

2 pkgs affected

🐘getkirby/cms🐘getkirby/cms

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

TL;DR

This vulnerability only affects Kirby sites that use the Xml data handler (e.g. Data::encode($string, 'xml')) or the Xml::create(), Xml::tag() or Xml::value() method(s) in site or plugin code. The Kirby core does not use any of the affected methods.

If consumers use an affected method and cannot rule out input to these methods controlled by an attacker, Kirby strongly recommends that they update to a patch release.

Introduction

XML strings contain structured data in tags and attributes. Depending on the used XML schema, this data can carry specific meaning that can lead to actions in other systems that parse and act on the XML data. Tags and attributes are detected based on their specific syntax, which includes characters such as <, >, ", and &. If these characters are to be used verbatim in text within the XML string, they can be escaped using a <![CDATA[ ]]> block.

XML injection is an attack on a system generating or parsing XML files. By injecting special characters into input data, XML output with a malicious meaning could be generated by a vulnerable system.

Impact

Kirby's Xml::value() method has special handling for <![CDATA[ ]]> blocks. If the input value is already valid CDATA, it is not escaped a second time but allowed to pass through. However it was possible to trick this check into allowing values that only contained a valid CDATA block but also contained other structured data outside of the CDATA block. This structured data would then also be allowed to pass through, circumventing the value protection.

The Xml::value() method is used in Xml::tag(), Xml::create() and in the Xml data handler (e.g. Data::encode($string, 'xml')).

Both the vulnerable methods and the data handler are not used in the Kirby core. However they may be used in site or plugin code, e.g. to create XML strings from input data. If those generated files are passed to another implementation that assigns specific meaning to the XML schema, manipulation of this system's behavior is possible.

Kirby sites that don't use XML generation in site or plugin code are not affected.

Patches

The problem has been patched in Kirby 4.9.0 and Kirby 5.4.0. Please update to one of these or a later version to fix the vulnerability.

In all of the mentioned releases, Kirby has added additional checks that only allow unchanged CDATA passthrough if the entire string is made up of valid CDATA blocks and no structured data. This protects all uses of the method against the described vulnerability.

Credits

Kirby thanks to Patrick Falb (@dapatrese) at FORMER 03 for responsibly reporting the identified issue.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`getkirby/cms`	all versions	4.9.0
🐘Packagist	`getkirby/cms`	≥ 5.0.0&&< 5.4.0	5.4.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getkirby/cms. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update getkirby/cms to 4.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9wfj-c55w-j9qr is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-9wfj-c55w-j9qr is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-9wfj-c55w-j9qr. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### TL;DR This vulnerability only affects Kirby sites that use the `Xml` data handler (e.g. `Data::encode($string, 'xml')`) or the `Xml::create()`, `Xml::tag()` or `Xml::value()` method(s) in site or plugin code. The Kirby core does not use any of the affected methods. If consumers use an affected method and cannot rule out input to these methods controlled by an attacker, Kirby strongly recommends that they update to a patch release. ---- ### Introduction XML strings contain structured data in tags and attributes. Depending on the used XML schema, this data can carry specific meaning tha

O3 Security · Impact-Aware SCA

Is GHSA-9wfj-c55w-j9qr in your dependencies?

O3 detects GHSA-9wfj-c55w-j9qr across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works