GHSA-42fc-7w97-8vrc is a medium-severity (CVSS 4.4) vulnerability in org.xwiki.contrib.plantuml:macro-plantuml-macro. O3 Security confirms whether GHSA-42fc-7w97-8vrc is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
XWiki PlantUML Macro Vulnerable to Server-Side Request Forgery (SSRF) via 'server' parameter
Real-World Exposure
org.xwiki.contrib.plantuml:macro-plantuml-macroReal-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 PlantUML Macro is vulnerable to Server-Side Request Forgery (SSRF). The macro allows users to specify an alternative PlantUML server via the server parameter. However, the application does not validate the supplied URL. An attacker can supply an internal IP address or a malicious external URL. The XWiki server will attempt to connect to this URL to "render" the diagram.
This issue affects all versions of the Plant UML Macro extension till version 2.4 included.
Patches
Version 2.4.1 of the Plant UML Macro extension fixes the issue by verifying if the supplied server domain matches one of the trusted domain configured inside of XWiki.
Workarounds
Protect the XWiki server by placing it in a DMZ so that it cannot access any other internal servers.
Resources
The issue was fixed in PLANTUML-25 by the commit c8b19bda93058794e04c8862fc7ca85c59b5fe5c.
For more information
If there are any questions or comments about this advisory:
- Open an issue in JIRA XWiki.org
- Send an email to Security Mailing List
Attribution
The issue was reported by Łukasz Rybak.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.xwiki.contrib.plantuml:macro-plantuml-macro | all versions | 2.4.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.contrib.plantuml:macro-plantuml-macro. 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.contrib.plantuml:macro-plantuml-macro to 2.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-42fc-7w97-8vrc 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 GHSA-42fc-7w97-8vrc 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-42fc-7w97-8vrc. 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-42fc-7w97-8vrc in your dependencies?
O3 detects GHSA-42fc-7w97-8vrc across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.