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        "cveId": "CVE-2026-109855",
        "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
        "state": "PUBLISHED",
        "assignerShortName": "openjs",
        "dateReserved": "2026-10-13T07:28:59.621Z",
        "datePublished": "2026-10-15T08:12:51.245Z",
        "dateUpdated": "2026-10-15T14:22:28.644Z"
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                    "lang": "en",
                    "value": "undici is an HTTP client library for Node.js. In versions 8.11.0 and 8.11.1, its experimental WebSocket client, which is enabled by default when HTTP/2 is allowed, mishandles a failed WebSocket handshake over HTTP/2: the request is already marked completed, so the abort becomes a no-op and the underlying HTTP/2 stream is left open with no error listener. When a malicious server then destroys the connection, the orphaned stream emits an unhandled error and the Node.js process exits. A remote, unauthenticated server can therefore crash any client that opens a WebSocket to it over HTTP/2, resulting in a denial of service. The issue is fixed in undici 8.11.2, and users should upgrade to 8.11.2 or later. As a workaround, set allowH2 to false to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers.",
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                            "value": "undici is an HTTP client library for Node.js. In versions 8.11.0 and 8.11.1, its experimental WebSocket client, which is enabled by default when HTTP/2 is allowed, mishandles a failed WebSocket handshake over HTTP/2: the request is already marked completed, so the abort becomes a no-op and the underlying HTTP/2 stream is left open with no error listener. When a malicious server then destroys the connection, the orphaned stream emits an unhandled error and the Node.js process exits. A remote, unauthenticated server can therefore crash any client that opens a WebSocket to it over HTTP/2, resulting in a denial of service. The issue is fixed in undici 8.11.2, and users should upgrade to 8.11.2 or later. As a workaround, set allowH2 to false to disable HTTP/2 for WebSocket connections, or avoid opening WebSocket connections to untrusted servers."
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                    "url": "https://github.com/nodejs/undici/security/advisories/GHSA-qq8j-7v2v-3rwp"
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            "title": "undici WebSocket client vulnerable to Denial of Service via failed HTTP/2 handshake",
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