{"id":"CVE-2022-21676","aliases":["GHSA-273r-mgr4-v34f"],"url":"https://o3.security/vulnerability/CVE-2022-21676","summary":"Uncaught Exception in engine.io","details":"### Impact\n\nA specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.\n\n> RangeError: Invalid WebSocket frame: RSV2 and RSV3 must be clear\n>   at Receiver.getInfo (/.../node_modules/ws/lib/receiver.js:176:14)\n>   at Receiver.startLoop (/.../node_modules/ws/lib/receiver.js:136:22)\n>   at Receiver._write (/.../node_modules/ws/lib/receiver.js:83:10)\n>   at writeOrBuffer (internal/streams/writable.js:358:12)\n\nThis impacts all the users of the [`engine.io`](https://www.npmjs.com/package/engine.io) package starting from version `4.0.0`, including those who uses depending packages like [`socket.io`](https://www.npmjs.com/package/socket.io).\n\n### Patches\n\nA fix has been released for each major branch:\n\n| Version range | Fixed version |\n| --- | --- |\n| `engine.io@4.x.x` | `4.1.2` |\n| `engine.io@5.x.x` | `5.2.1` |\n| `engine.io@6.x.x` | `6.1.1` |\n\nPrevious versions (`< 4.0.0`) are not impacted.\n\nFor `socket.io` users:\n\n| Version range | `engine.io` version | Needs minor update? |\n| --- | --- | --- |\n| `socket.io@4.4.x` | `~6.1.0` | -\n| `socket.io@4.3.x` | `~6.0.0` | Please upgrade to `socket.io@4.4.x`\n| `socket.io@4.2.x` | `~5.2.0` | -\n| `socket.io@4.1.x` | `~5.1.1` | Please upgrade to `socket.io@4.4.x`\n| `socket.io@4.0.x` | `~5.0.0` | Please upgrade to `socket.io@4.4.x`\n| `socket.io@3.1.x` | `~4.1.0` | -\n| `socket.io@3.0.x` | `~4.0.0` | Please upgrade to `socket.io@3.1.x` or `socket.io@4.4.x` (see [here](https://socket.io/docs/v4/migrating-from-3-x-to-4-0/))\n\nIn most cases, running `npm audit fix` should be sufficient. You can also use  `npm update engine.io --depth=9999`.\n\n### Workarounds\n\nThere is no known workaround except upgrading to a safe version.\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n* Open an issue in [`engine.io`](https://github.com/socketio/engine.io)\n\nThanks to Marcus Wejderot from Mevisio for the responsible disclosure.\n","published":"2022-01-12T18:25:15Z","modified":"2026-10-28T02:30:30.600749814Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.0276,"percentile":0.85528,"asOf":"2026-09-16"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"engine.io","fixedVersion":"4.1.2"},{"ecosystem":"npm","name":"engine.io","fixedVersion":"5.2.1"},{"ecosystem":"npm","name":"engine.io","fixedVersion":"6.1.1"}],"fix":{"url":"https://github.com/socketio/engine.io/commit/66f889fc1d966bf5bfa0de1939069153643874ab","label":"socketio/engine.io@66f889f"},"references":[{"type":"WEB","url":"https://github.com/socketio/engine.io/releases/tag/4.1.2"},{"type":"WEB","url":"https://github.com/socketio/engine.io/releases/tag/5.2.1"},{"type":"WEB","url":"https://github.com/socketio/engine.io/releases/tag/6.1.1"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/21xxx/CVE-2022-21676.json"},{"type":"ADVISORY","url":"https://github.com/socketio/engine.io/security/advisories/GHSA-273r-mgr4-v34f"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-21676"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20220209-0002/"},{"type":"FIX","url":"https://github.com/socketio/engine.io/commit/66f889fc1d966bf5bfa0de1939069153643874ab"},{"type":"FIX","url":"https://github.com/socketio/engine.io/commit/a70800d7e96da32f6e6622804ef659ebc58659db"},{"type":"FIX","url":"https://github.com/socketio/engine.io/commit/c0e194d44933bd83bf9a4b126fca68ba7bf5098c"},{"type":"WEB","url":"https://github.com/socketio/engine.io"},{"type":"WEB","url":"https://security.netapp.com/advisory/ntap-20220209-0002"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-28T02:30:30.600749814Z"}}