GHSA-gw55-jm4h-x339
CRITICALGHSA-gw55-jm4h-x339 is a critical-severity (CVSS 9) CWE-297 vulnerability in org.java-websocket:Java-WebSocket. O3 Security confirms whether GHSA-gw55-jm4h-x339 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Improper Validation of Certificate with Host Mismatch in Java-WebSocket
Real-World Exposure
org.java-websocket:Java-WebSocketReal-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
The Java-WebSocket Client does not perform hostname verification.
- This means that SSL certificates of other hosts are accepted as long as they are trusted. To exploit this vulnerability an attacker has to perform a man-in-the-middle (MITM) attack between a Java application using the Java-WebSocket Client and an WebSocket server it's connecting to.
- TLS normally protects users and systems against MITM attacks, it cannot if certificates from other trusted hosts are accepted by the client.
For more information see: CWE-297: Improper Validation of Certificate with Host Mismatch - https://cwe.mitre.org/data/definitions/297.html
Important note
The OWASP Dependency-Check (https://jeremylong.github.io/DependencyCheck/index.html) may report that a dependency of your project is affected by this security vulnerability, but you don't use this lib. This is caused by the fuzzy search in the OWASP implementation. Check out this issue (https://github.com/TooTallNate/Java-WebSocket/issues/1019#issuecomment-628507934) for more information and a way to suppress the warning.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.java-websocket:Java-WebSocket | all versions | 1.5.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.java-websocket:Java-WebSocket. 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.java-websocket:Java-WebSocket to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gw55-jm4h-x339 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-gw55-jm4h-x339 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-gw55-jm4h-x339. 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-gw55-jm4h-x339 in your dependencies?
O3 detects GHSA-gw55-jm4h-x339 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.