Socket.IO version 2.5.0 represents an incremental update over the 2.4.1 release, offering developers refinements and potentially crucial bug fixes within the popular real-time communication library. A key observable difference lies in the updated dependencies, most notably engine.io, which jumps from version 3.5.0 in 2.4.1 to 3.6.0 in 2.5.0. This dependency update often reflects improvements in the underlying transport layer responsible for handling connections and data transfer, possibly leading to performance enhancements or better handling of specific network conditions. The socket.io-client dependency also sees an increment, moving from version 2.4.0 to 2.5.0, ensuring compatibility between the server and client components and incorporating any client-side bug fixes and feature additions that may complement the server-side improvements. The package size also sees a slight increase which combined with other differences might reflect minor feature additions. Developers should note that while the core dependencies socket.io-parser and socket.io-adapter remain unchanged, the updates to engine.io and socket.io-client could necessitate adjustments in their client-side code or server configurations to fully leverage the benefits of version 2.5.0. The later release date of 2.5.0, June 2022 compared to January 2021 for version 2.4.1, suggests that developers seeking the most up-to-date features and bug fixes should prioritize upgrading to the newer version.
All the vulnerabilities related to the version 2.5.0 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.
Regular Expression Denial of Service in debug
Affected versions of debug are vulnerable to regular expression denial of service when untrusted user input is passed into the o formatter.
As it takes 50,000 characters to block the event loop for 2 seconds, this issue is a low severity issue.
This was later re-introduced in version v3.2.0, and then repatched in versions 3.2.7 and 4.3.1.
Version 2.x.x: Update to version 2.6.9 or later. Version 3.1.x: Update to version 3.1.0 or later. Version 3.2.x: Update to version 3.2.7 or later. Version 4.x.x: Update to version 4.3.1 or later.
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.
parse-uri Regular expression Denial of Service (ReDoS)
An issue in parse-uri v1.0.9 allows attackers to cause a Regular expression Denial of Service (ReDoS) via a crafted URL.
async function exploit() {
const parseuri = require("parse-uri");
// This input is designed to cause excessive backtracking in the regex
const craftedInput = 'http://example.com/' + 'a'.repeat(30000) + '?key=value';
const result = await parseuri(craftedInput);
}
await exploit();