CVE-2025-66474

XWiki vulnerable to remote code execution through insufficient protection against {{/html}} injection

Workarounds

We're not aware of any workarounds except for upgrading the affected module to a version with a fix.

Any user who can edit their own user profile or any other document can execute arbitrary script macros including Groovy and Python macros that allow remote code execution including unrestricted read and write access to all wiki contents. The reason is that rendering output is included as content of HTML macros with insufficient escaping, and it is thus possible to close the HTML macro and inject script macros that are executed with programming rights. To demonstrate, the content {{html}}{{/html {{/html}}}} can be inserted into any field of the user profile that supports wiki syntax like the "About" field. If this leads to the display of raw HTML, the instance is vulnerable.

Untrusted input is evaluated as executable code within the application's runtime environment. Typical impact: arbitrary code execution within the application's privilege context.

Kodem intelligence

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This problem has been patched by extending the escaping introduced by XRENDERING-693 to also cover closing HTML macros that have spaces after the macro name in XWiki 16.10.10, 17.4.3 and 17.6.0RC1. A similar fix has been applied in org.xwiki.platform:xwiki-platform-oldcore as an extra safety net, see XWIKI-23378. At this point, we're not aware that this extra safety net would be required for security.

The patch also fixes the injection of opening HTML macro syntaxes, e.g., with {{html}}{{html{{/html}}}} which disrupts the rendering of the user profile but for which we haven't found any further security impact apart from the disruption of the UI.

1. What is CVE-2025-66474? CVE-2025-66474 is a high-severity code injection vulnerability in org.xwiki.rendering:xwiki-rendering-xml (maven), affecting versions < 16.10.10. It is fixed in 16.10.10, 17.4.3, 17.6.0-rc-1. Untrusted input is evaluated as executable code within the application's runtime environment.
2. Which versions of org.xwiki.rendering:xwiki-rendering-xml are affected by CVE-2025-66474? org.xwiki.rendering:xwiki-rendering-xml (maven) versions < 16.10.10 is affected.
3. Is there a fix for CVE-2025-66474? Yes. CVE-2025-66474 is fixed in 16.10.10, 17.4.3, 17.6.0-rc-1. Upgrade to this version or later.
4. Is CVE-2025-66474 exploitable, and should I be worried? Whether CVE-2025-66474 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
5. What actually determines whether CVE-2025-66474 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
6. How do I fix CVE-2025-66474?
   • Upgrade org.xwiki.rendering:xwiki-rendering-xml to 16.10.10 or later
   • Upgrade org.xwiki.rendering:xwiki-rendering-xml to 17.4.3 or later
   • Upgrade org.xwiki.rendering:xwiki-rendering-xml to 17.6.0-rc-1 or later

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