GHSA-c885-89fw-55qr
CRITICALorg.xwiki.platform:xwiki-platform-rendering-macro-rss Cross-site Scripting vulnerability
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
org.xwiki.platform:xwiki-core-rendering-macro-rss☕org.xwiki.platform:xwiki-platform-rendering-macro-rssReal-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
Impact
The RSS macro that is bundled in XWiki included the content of the feed items without any cleaning in the HTML output when the parameter content was set to true. This allowed arbitrary HTML and in particular also JavaScript injection and thus cross-site scripting (XSS) by specifying an RSS feed with malicious content. With the interaction of a user with programming rights, this could be used to execute arbitrary actions in the wiki, including privilege escalation, remote code execution, information disclosure, modifying or deleting content and sabotaging the wiki.
The issue can be reproduced by inserting the following XWiki syntax in any wiki page like the user account:
{{rss feed="https://xssrss.blogspot.com/feeds/posts/default?alt=rss" content="true" /}}
If an alert is displayed when viewing the page, the wiki is vulnerable.
Patches
The issue has been patched in XWiki 14.6 RC1, the content of the feed is now properly cleaned before being displayed.
Workarounds
If the RSS macro isn't used in the wiki, the macro can be uninstalled by deleting WEB-INF/lib/xwiki-platform-rendering-macro-rss-XX.jar, where XX is XWiki's version, in the web application's directory.
References
- https://github.com/xwiki/xwiki-platform/commit/5c7ebe47c2897e92d8f04fe2e15027e84dc3ec03
- https://jira.xwiki.org/browse/XWIKI-19671
For more information
If you have any questions or comments about this advisory:
- Open an issue in Jira XWiki.org
- Email us at Security Mailing List
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.xwiki.platform:xwiki-core-rendering-macro-rss | ≥ 1.8 | No fix |
| ☕Maven | org.xwiki.platform:xwiki-platform-rendering-macro-rss | all versions | 14.6-rc-1 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.platform:xwiki-core-rendering-macro-rss. 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
No patched version of org.xwiki.platform:xwiki-core-rendering-macro-rss has shipped for GHSA-c885-89fw-55qr yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
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-c885-89fw-55qr 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-c885-89fw-55qr. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-c885-89fw-55qr in your dependencies?
O3 detects GHSA-c885-89fw-55qr across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.