org.xwiki.contrib.markdown:syntax-markdown-commonmark12 vulnerable to XSS via Markdown content

Exploitation

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

CVSS

9.0 · CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

EPSS

• CVE-2025-46558: 0.49% estimated exploitation activity in the next 30 days; percentile 41.91 (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.

Impact The Markdown syntax is vulnerable to XSS through HTML. In particular, using Markdown syntax, it's possible for any user to embed Javascript code that will then be executed on the browser of any other user visiting either the document or the comment that contains it. In the instance that this code is executed by a user with admins or programming rights, this issue compromises the confidentiality, integrity and availability of the whole XWiki installation. To reproduce, on an instance where the CommonMark Markdown Syntax 1.2 extension is installed, log in as a user without script rights. Edit a document and set its syntax to Markdown. Then , add the content <scriptalert("XSS")</script and refresh the page. If an alert appears containing "XSS", then the instance is vulnerable. Patches This has been patched in version 8.9 of the CommonMark Markdown Syntax 1.2 extension. Workarounds We're not aware of any workaround except upgrading. References…

Published by the source

30 Apr 2025, 16:53 UTC

Last modified by the source

1 May 2025, 13:30 UTC

Source last checked

26 Oct 2026, 16:35 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8g2j-rhfh-hq3r

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# Patch Next advisory brief: CVE-2025-46558

Advisory: org.xwiki.contrib.markdown:syntax-markdown-commonmark12 vulnerable to XSS via Markdown content
IDs: CVE-2025-46558, GHSA-8g2j-rhfh-hq3r
Record: https://patchnext.com/advisories/cve-2025-46558 (revision 1, source checked 26 Oct 2026, 16:35 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.xwiki.contrib.markdown:syntax-markdown-commonmark12 8.9. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.xwiki.contrib.markdown:syntax-markdown-commonmark12: affected >= 8.2, < 8.9; fixed in 8.9

## Suggested inspection (read-only)
- Maven org.xwiki.contrib.markdown:syntax-markdown-commonmark12: 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 org.xwiki.contrib.markdown:syntax-markdown-commonmark12.
- 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-8g2j-rhfh-hq3r (GitHub-reviewed advisory GHSA-8g2j-rhfh-hq3r lists affected ranges: Maven org.xwiki.contrib.markdown:syntax-markdown-commonmark12 >=8.2 <8.9)

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