CVE-2025-53835 is a critical-severity (CVSS 9) Cross-site Scripting (XSS) vulnerability in org.xwiki.rendering:xwiki-rendering-syntax-xhtml. O3 Security confirms whether CVE-2025-53835 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
XWiki Rendering is vulnerable to XSS attacks through insecure XHTML syntax
Real-World Exposure
org.xwiki.rendering:xwiki-rendering-syntax-xhtmlReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
XWiki Rendering is a generic rendering system that converts textual input in a given syntax (wiki syntax, HTML, etc) into another syntax (XHTML, etc). Starting in version 5.4.5 and prior to version 14.10, the XHTML syntax depended on the xdom+xml/current syntax which allows the creation of raw blocks that permit the insertion of arbitrary HTML content including JavaScript. This allows XSS attacks for users who can edit a document like their user profile (enabled by default). This has been fixed in version 14.10 by removing the dependency on the xdom+xml/current syntax from the XHTML syntax. Note that the xdom+xml syntax is still vulnerable to this attack. As it's main purpose is testing and its use is quite difficult, this syntax shouldn't be installed or used on a regular wiki. There are no known workarounds apart from upgrading.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.xwiki.rendering:xwiki-rendering-syntax-xhtml | ≥ 5.4.5&&< 14.10 | 14.10 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.rendering:xwiki-rendering-syntax-xhtml. 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 org.xwiki.rendering:xwiki-rendering-syntax-xhtml to 14.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-53835 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 CVE-2025-53835 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 CVE-2025-53835. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-53835 in your dependencies?
O3 detects CVE-2025-53835 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.