GHSA-33ph-fccm-39pj
GHSA-33ph-fccm-39pj is a CWE-770 vulnerability in websocket-driver. O3 Security confirms whether GHSA-33ph-fccm-39pj is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
websocket-driver: Resource limit bypass via message compression
Blast Radius
websocket-driverReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Impact
If this library is used in tandem with the permessage-deflate extension, a WebSocket server or client can be made to accept messages that are larger than the configured maximum message size. This is because this limit is checked against the message frames' length headers, which give the size of the compressed data, not the size after decompression. This can lead to applications accepting larger messages than expected and exceeding their intended resource usage.
Patches
The issue has been patched in version 0.8.1, by checking the length of messages after they are processed by incoming extensions. All users should upgrade to this version.
Workarounds
No known workarounds exist.
Acknowledgements
This issue was discovered and reported by Pranjali Thakur, DepthFirst Security Research Team.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | websocket-driver | all versions | 0.8.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for websocket-driver. 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 websocket-driver to 0.8.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-33ph-fccm-39pj 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-33ph-fccm-39pj 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-33ph-fccm-39pj. 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-33ph-fccm-39pj in your dependencies?
O3 detects GHSA-33ph-fccm-39pj across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.