Socket.IO version 4.3.1 represents a minor update to the popular real-time communication library, building upon the foundation established by version 4.3.0. Both versions share the same core dependencies, including debug, accepts, base64id, engine.io, socket.io-parser, and socket.io-adapter, ensuring a consistent base functionality related to debugging, content negotiation, unique ID generation, the underlying Engine.IO transport, socket parsing, and adapter management, respectively. The developer experience remains largely the same, retaining key development dependencies such as nyc for code coverage, tsd for type definition testing, mocha for unit testing, rimraf for file removal, ts-node for TypeScript execution, prettier for code formatting, and typescript for typescript type checking, helping guarantee a high-quality, maintainable codebase.
The primary discernible change lies in the updated version of the socket.io-client development dependency: 4.3.1 is used instead of 4.3.0, suggesting internal updates or bug fixes within the client library that might complement the server-side framework. This update comes accompanied by a slight increase in the unpacked size of the package, from 976104 bytes to 978996 bytes, likely a consequence of the changes within the client library or minor adjustments made to the core server code. Developers already using version 4.3.0 should review the changelog of socket.io-client to understand the specific improvements and potential breaking changes, if any. The release date difference indicates that version 4.3.1 was released two days after 4.3.0, this small release window reinforces the idea that 4.3.1 is a patch version with a fast roll out of fixes.
All the vulnerabilities related to the version 4.3.1 of the package
socket.io has an unhandled 'error' event
A specially crafted Socket.IO packet can trigger an uncaught exception on the Socket.IO server, thus killing the Node.js process.
node:events:502
throw err; // Unhandled 'error' event
^
Error [ERR_UNHANDLED_ERROR]: Unhandled error. (undefined)
at new NodeError (node:internal/errors:405:5)
at Socket.emit (node:events:500:17)
at /myapp/node_modules/socket.io/lib/socket.js:531:14
at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
code: 'ERR_UNHANDLED_ERROR',
context: undefined
}
| Version range | Needs minor update? |
|------------------|------------------------------------------------|
| 4.6.2...latest | Nothing to do |
| 3.0.0...4.6.1 | Please upgrade to socket.io@4.6.2 (at least) |
| 2.3.0...2.5.0 | Please upgrade to socket.io@2.5.1 |
This issue is fixed by https://github.com/socketio/socket.io/commit/15af22fc22bc6030fcead322c106f07640336115, included in socket.io@4.6.2 (released in May 2023).
The fix was backported in the 2.x branch today: https://github.com/socketio/socket.io/commit/d30630ba10562bf987f4d2b42440fc41a828119c
As a workaround for the affected versions of the socket.io package, you can attach a listener for the "error" event:
io.on("connection", (socket) => {
socket.on("error", () => {
// ...
});
});
If you have any questions or comments about this advisory:
Thanks a lot to Paul Taylor for the responsible disclosure.
Uncaught Exception in engine.io
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 (/.../node_modules/ws/lib/receiver.js:176:14) at Receiver.startLoop (/.../node_modules/ws/lib/receiver.js:136:22) at Receiver._write (/.../node_modules/ws/lib/receiver.js:83:10) at writeOrBuffer (internal/streams/writable.js:358:12)
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.
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:
engine.ioThanks to Marcus Wejderot from Mevisio for the responsible disclosure.
Uncaught exception in engine.io
A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.
events.js:292
throw er; // Unhandled 'error' event
^
Error: read ECONNRESET
at TCP.onStreamRead (internal/stream_base_commons.js:209:20)
Emitted 'error' event on Socket instance at:
at emitErrorNT (internal/streams/destroy.js:106:8)
at emitErrorCloseNT (internal/streams/destroy.js:74:3)
at processTicksAndRejections (internal/process/task_queues.js:80:21) {
errno: -104,
code: 'ECONNRESET',
syscall: 'read'
}
This impacts all the users of the engine.io package, including those who uses depending packages like socket.io.
A fix has been released today (2022/11/20):
| Version range | Fixed version |
|-------------------|---------------|
| engine.io@3.x.y | 3.6.1 |
| engine.io@6.x.y | 6.2.1 |
For socket.io users:
| Version range | engine.io version | Needs minor update? |
|-----------------------------|---------------------|--------------------------------------------------------------------------------------------------------|
| socket.io@4.5.x | ~6.2.0 | npm audit fix should be sufficient |
| socket.io@4.4.x | ~6.1.0 | Please upgrade to socket.io@4.5.x |
| socket.io@4.3.x | ~6.0.0 | Please upgrade to socket.io@4.5.x |
| socket.io@4.2.x | ~5.2.0 | Please upgrade to socket.io@4.5.x |
| socket.io@4.1.x | ~5.1.1 | Please upgrade to socket.io@4.5.x |
| socket.io@4.0.x | ~5.0.0 | Please upgrade to socket.io@4.5.x |
| socket.io@3.1.x | ~4.1.0 | Please upgrade to socket.io@4.5.x (see here) |
| socket.io@3.0.x | ~4.0.0 | Please upgrade to socket.io@4.5.x (see here) |
| socket.io@2.5.0 | ~3.6.0 | npm audit fix should be sufficient |
| socket.io@2.4.x and below | ~3.5.0 | Please upgrade to socket.io@2.5.0 |
There is no known workaround except upgrading to a safe version.
If you have any questions or comments about this advisory:
engine.ioThanks to Jonathan Neve for the responsible disclosure.
engine.io Uncaught Exception vulnerability
A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.
TypeError: Cannot read properties of undefined (reading 'handlesUpgrades')
at Server.onWebSocket (build/server.js:515:67)
This impacts all the users of the engine.io package, including those who uses depending packages like socket.io.
A fix has been released today (2023/05/02): 6.4.2
This bug was introduced in version 5.1.0 and included in version 4.1.0 of the socket.io parent package. Older versions are not impacted.
For socket.io users:
| Version range | engine.io version | Needs minor update? |
|-----------------------------|---------------------|--------------------------------------------------------------------------------------------------------|
| socket.io@4.6.x | ~6.4.0 | npm audit fix should be sufficient |
| socket.io@4.5.x | ~6.2.0 | Please upgrade to socket.io@4.6.x |
| socket.io@4.4.x | ~6.1.0 | Please upgrade to socket.io@4.6.x |
| socket.io@4.3.x | ~6.0.0 | Please upgrade to socket.io@4.6.x |
| socket.io@4.2.x | ~5.2.0 | Please upgrade to socket.io@4.6.x |
| socket.io@4.1.x | ~5.1.1 | Please upgrade to socket.io@4.6.x |
| socket.io@4.0.x | ~5.0.0 | Not impacted |
| socket.io@3.1.x | ~4.1.0 | Not impacted |
| socket.io@3.0.x | ~4.0.0 | Not impacted |
| socket.io@2.5.0 | ~3.6.0 | Not impacted |
| socket.io@2.4.x and below | ~3.5.0 | Not impacted |
There is no known workaround except upgrading to a safe version.
If you have any questions or comments about this advisory:
engine.ioThanks to Thomas Rinsma from Codean for the responsible disclosure.
ws affected by a DoS when handling a request with many HTTP headers
A request with a number of headers exceeding theserver.maxHeadersCount threshold could be used to crash a ws server.
const http = require('http');
const WebSocket = require('ws');
const wss = new WebSocket.Server({ port: 0 }, function () {
const chars = "!#$%&'*+-.0123456789abcdefghijklmnopqrstuvwxyz^_`|~".split('');
const headers = {};
let count = 0;
for (let i = 0; i < chars.length; i++) {
if (count === 2000) break;
for (let j = 0; j < chars.length; j++) {
const key = chars[i] + chars[j];
headers[key] = 'x';
if (++count === 2000) break;
}
}
headers.Connection = 'Upgrade';
headers.Upgrade = 'websocket';
headers['Sec-WebSocket-Key'] = 'dGhlIHNhbXBsZSBub25jZQ==';
headers['Sec-WebSocket-Version'] = '13';
const request = http.request({
headers: headers,
host: '127.0.0.1',
port: wss.address().port
});
request.end();
});
The vulnerability was fixed in ws@8.17.1 (https://github.com/websockets/ws/commit/e55e5106f10fcbaac37cfa89759e4cc0d073a52c) and backported to ws@7.5.10 (https://github.com/websockets/ws/commit/22c28763234aa75a7e1b76f5c01c181260d7917f), ws@6.2.3 (https://github.com/websockets/ws/commit/eeb76d313e2a00dd5247ca3597bba7877d064a63), and ws@5.2.4 (https://github.com/websockets/ws/commit/4abd8f6de4b0b65ef80b3ff081989479ed93377e)
In vulnerable versions of ws, the issue can be mitigated in the following ways:
--max-http-header-size=size and/or the maxHeaderSize options so that no more headers than the server.maxHeadersCount limit can be sent.server.maxHeadersCount to 0 so that no limit is applied.The vulnerability was reported by Ryan LaPointe in https://github.com/websockets/ws/issues/2230.
cookie accepts cookie name, path, and domain with out of bounds characters
The cookie name could be used to set other fields of the cookie, resulting in an unexpected cookie value. For example, serialize("userName=<script>alert('XSS3')</script>; Max-Age=2592000; a", value) would result in "userName=<script>alert('XSS3')</script>; Max-Age=2592000; a=test", setting userName cookie to <script> and ignoring value.
A similar escape can be used for path and domain, which could be abused to alter other fields of the cookie.
Upgrade to 0.7.0, which updates the validation for name, path, and domain.
Avoid passing untrusted or arbitrary values for these fields, ensure they are set by the application instead of user input.
Insufficient validation when decoding a Socket.IO packet
A specially crafted Socket.IO packet can trigger an uncaught exception on the Socket.IO server, thus killing the Node.js process.
TypeError: Cannot convert object to primitive value
at Socket.emit (node:events:507:25)
at .../node_modules/socket.io/lib/socket.js:531:14
A fix has been released today (2023/05/22):
socket.io-parser@4.2.3socket.io-parser@3.4.3Another fix has been released for the 3.3.x branch:
| socket.io version | socket.io-parser version | Needs minor update? |
|---------------------|---------------------------------------------------------------------------------------------------------|--------------------------------------|
| 4.5.2...latest | ~4.2.0 (ref) | npm audit fix should be sufficient |
| 4.1.3...4.5.1 | ~4.1.1 (ref) | Please upgrade to socket.io@4.6.x |
| 3.0.5...4.1.2 | ~4.0.3 (ref) | Please upgrade to socket.io@4.6.x |
| 3.0.0...3.0.4 | ~4.0.1 (ref) | Please upgrade to socket.io@4.6.x |
| 2.3.0...2.5.0 | ~3.4.0 (ref) | npm audit fix should be sufficient |
There is no known workaround except upgrading to a safe version.
If you have any questions or comments about this advisory:
Thanks to @rafax00 for the responsible disclosure.