A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.
RangeError: Invalid WebSocket frame: RSV2 and RSV3 must be clear at Receiver.getInfo (/.../nodemodules/ws/lib/receiver.js:176:14) at Receiver.startLoop (/.../nodemodules/ws/lib/receiver.js:136:22) at Receiver.write (/.../nodemodules/ws/lib/receiver.js:83:10) at writeOrBuffer (internal/streams/writable.js:358:12)
This impacts all the users of the <code>engine.io</code> package starting from version 4.0.0, including those who uses depending packages like <code>socket.io</code>.
A fix has been released for each major branch:
| Version range | Fixed version |
| --- | --- |
| engine.io@4.x.x | 4.1.2 |
| engine.io@5.x.x | 5.2.1 |
| engine.io@6.x.x | 6.1.1 |
Previous versions (< 4.0.0) are not impacted.
For socket.io users:
| Version range | engine.io version | Needs minor update? |
| --- | --- | --- |
| socket.io@4.4.x | ~6.1.0 | -
| socket.io@4.3.x | ~6.0.0 | Please upgrade to socket.io@4.4.x
| socket.io@4.2.x | ~5.2.0 | -
| socket.io@4.1.x | ~5.1.1 | Please upgrade to socket.io@4.4.x
| socket.io@4.0.x | ~5.0.0 | Please upgrade to socket.io@4.4.x
| socket.io@3.1.x | ~4.1.0 | -
| socket.io@3.0.x | ~4.0.0 | Please upgrade to socket.io@3.1.x or socket.io@4.4.x (see here)
In most cases, running npm audit fix should be sufficient. You can also use npm update engine.io --depth=9999.
There is no known workaround except upgrading to a safe version.
If you have any questions or comments about this advisory:
Thanks to Marcus Wejderot from Mevisio for the responsible disclosure.
{
"severity": "HIGH",
"github_reviewed": true,
"cwe_ids": [
"CWE-754",
"CWE-755"
],
"nvd_published_at": "2022-01-12T19:15:00Z",
"github_reviewed_at": "2022-01-12T19:26:23Z"
}