ghsa-6fc8-4gx4-v693
Vulnerability from github
Impact
A specially crafted value of the Sec-Websocket-Protocol header can be used to significantly slow down a ws server.
Proof of concept
```js for (const length of [1000, 2000, 4000, 8000, 16000, 32000]) { const value = 'b' + ' '.repeat(length) + 'x'; const start = process.hrtime.bigint();
value.trim().split(/ , /);
const end = process.hrtime.bigint();
console.log('length = %d, time = %f ns', length, end - start); } ```
Patches
The vulnerability was fixed in ws@7.4.6 (https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff) and backported to ws@6.2.2 (https://github.com/websockets/ws/commit/78c676d2a1acefbc05292e9f7ea0a9457704bf1b) and ws@5.2.3 (https://github.com/websockets/ws/commit/76d47c1479002022a3e4357b3c9f0e23a68d4cd2).
Workarounds
In vulnerable versions of ws, the issue can be mitigated by reducing the maximum allowed length of the request headers using the --max-http-header-size=size and/or the maxHeaderSize options.
Credits
The vulnerability was responsibly disclosed along with a fix in private by Robert McLaughlin from University of California, Santa Barbara.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "ws"
},
"ranges": [
{
"events": [
{
"introduced": "7.0.0"
},
{
"fixed": "7.4.6"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "ws"
},
"ranges": [
{
"events": [
{
"introduced": "6.0.0"
},
{
"fixed": "6.2.2"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "ws"
},
"ranges": [
{
"events": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.2.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-32640"
],
"database_specific": {
"cwe_ids": [
"CWE-345",
"CWE-400"
],
"github_reviewed": true,
"github_reviewed_at": "2021-05-28T18:18:04Z",
"nvd_published_at": "2021-05-25T19:15:00Z",
"severity": "MODERATE"
},
"details": "### Impact\n\nA specially crafted value of the `Sec-Websocket-Protocol` header can be used to significantly slow down a ws server.\n\n### Proof of concept\n\n```js\nfor (const length of [1000, 2000, 4000, 8000, 16000, 32000]) {\n const value = \u0027b\u0027 + \u0027 \u0027.repeat(length) + \u0027x\u0027;\n const start = process.hrtime.bigint();\n\n value.trim().split(/ *, */);\n\n const end = process.hrtime.bigint();\n\n console.log(\u0027length = %d, time = %f ns\u0027, length, end - start);\n}\n```\n\n### Patches\n\nThe vulnerability was fixed in ws@7.4.6 (https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff) and backported to ws@6.2.2 (https://github.com/websockets/ws/commit/78c676d2a1acefbc05292e9f7ea0a9457704bf1b) and ws@5.2.3 (https://github.com/websockets/ws/commit/76d47c1479002022a3e4357b3c9f0e23a68d4cd2).\n\n### Workarounds\n\nIn vulnerable versions of ws, the issue can be mitigated by reducing the maximum allowed length of the request headers using the [`--max-http-header-size=size`](https://nodejs.org/api/cli.html#cli_max_http_header_size_size) and/or the [`maxHeaderSize`](https://nodejs.org/api/http.html#http_http_createserver_options_requestlistener) options.\n\n### Credits\n\nThe vulnerability was responsibly disclosed along with a fix in private by [Robert McLaughlin](https://github.com/robmcl4) from University of California, Santa Barbara.\n",
"id": "GHSA-6fc8-4gx4-v693",
"modified": "2021-10-06T22:05:51Z",
"published": "2021-05-28T19:19:03Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/websockets/ws/security/advisories/GHSA-6fc8-4gx4-v693"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32640"
},
{
"type": "WEB",
"url": "https://github.com/websockets/ws/issues/1895"
},
{
"type": "WEB",
"url": "https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff"
},
{
"type": "PACKAGE",
"url": "https://github.com/websockets/ws"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread.html/rdfa7b6253c4d6271e31566ecd5f30b7ce1b8fb2c89d52b8c4e0f4e30@%3Ccommits.tinkerpop.apache.org%3E"
},
{
"type": "WEB",
"url": "https://security.netapp.com/advisory/ntap-20210706-0005"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"type": "CVSS_V3"
}
],
"summary": "ReDoS in Sec-Websocket-Protocol header"
}