XML External Entity (XXE) vulnerability in the XML data handler

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

6.8 · CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N

EPSS

• CVE-2023-38490: 1.70% estimated exploitation activity in the next 30 days; percentile 77.25 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

TL;DR This vulnerability only affects Kirby sites that use the Xml data handler (e.g. Data::decode($string, 'xml')) or the Xml::parse() method in site or plugin code. The Kirby core does not use any of the affected methods. If you use an affected method and cannot rule out XML input controlled by an attacker, we strongly recommend to update to a patch release. ---- Introduction XML External Entities (XXE) is a little used feature in the XML markup language that allows to include data from external files in an XML structure. If the name of the external file can be controlled by an attacker, this becomes a vulnerability that can be abused for various system impacts like the disclosure of internal or confidential data that is stored on the server (arbitrary file disclosure) or to perform network requests on behalf of the server (server-side request forgery, SSRF). Impact Kirby's Xml::parse() method used PHP's LIBXMLNOENT constant, which enabled the processing of XML external entities…

Published by the source

28 Jul 2023, 15:35 UTC

Last modified by the source

5 Nov 2023, 05:01 UTC

Source last checked

26 Oct 2026, 14:10 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-q386-w6fg-gmgp

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# Patch Next advisory brief: CVE-2023-38490

Advisory: XML External Entity (XXE) vulnerability in the XML data handler
IDs: CVE-2023-38490, GHSA-q386-w6fg-gmgp
Record: https://patchnext.com/advisories/cve-2023-38490 (revision 1, source checked 26 Oct 2026, 14:10 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: getkirby/cms 3.9.6, 3.8.4.1, 3.7.5.2, 3.6.6.3, 3.5.8.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist getkirby/cms: affected < 3.5.8.3; >= 3.6.0, < 3.6.6.3; >= 3.7.0, < 3.7.5.2; >= 3.8.0, < 3.8.4.1; >= 3.9.0, < 3.9.6; fixed in 3.8.4.1, 3.7.5.2, 3.6.6.3, 3.9.6, 3.5.8.3

## Suggested inspection (read-only)
- Packagist getkirby/cms: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on getkirby/cms.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-q386-w6fg-gmgp (GitHub-reviewed advisory GHSA-q386-w6fg-gmgp lists affected ranges: Packagist getkirby/cms >=0 =3.6.0 =3.7.0 =3.8.0 =3.9.0 <3.9.6)

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