Engine.IO is the implementation of transport-based cross-browser/cross-device bi-directional communication layer for Socket.IO. A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process. This impacts all the users of the `engine.io` package starting from version `4.0.0`, including those who uses depending packages like `socket.io`. Versions prior to `4.0.0` are not impacted. A fix has been released for each major branch, namely `4.1.2` for the `4.x.x` branch, `5.2.1` for the `5.x.x` branch, and `6.1.1` for the `6.x.x` branch. There is no known workaround except upgrading to a safe version.
| Package (Ecosystem) | Introduced | Fixed | Limit |
|---|---|---|---|
| engine.io(npm) | 4.0.0 | 4.1.2 | N/A |
| engine.io(npm) | 5.0.0 | 5.2.1 | N/A |
| engine.io(npm) | 6.0.0 | 6.1.1 | N/A |
CVSS Metrics
