GHSA-6fc8-4gx4-v693 ReDoS in Sec-Websocket-Protocol header

• npm ws: >= 7.0.0, < 7.4.6 → fixed in 7.4.6 • npm ws: >= 6.0.0, < 6.2.2 → fixed in 6.2.2 • npm ws: >= 5.0.0, < 5.2.3 → fixed in 5.2.3

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 [email protected] (https://github.com/websockets/ws/commit/00c425ec77993773d823f018f64a5c44e17023ff) and backported to [email protected] (https://github.com/websockets/ws/commit/78c676d2a1acefbc05292e9f7ea0a9457704bf1b) and [email protected] (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.