Vulnerability · Published Aug 13, 2026 · Assigned by GitHub_M
CVE-2026-73565@hono/node-server: Unauthenticated memory-leak DoS via aborted WebSocket handshake
Medium 5.3
In plain English
A medium-severity memory leak in node-server from honojs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
@hono/node-server allows running the Hono application on Node.js. From 2.0.0 until 2.0.10, a WebSocket upgrade request to an upgradeWebSocket route with a missing or malformed Sec-WebSocket-Key header causes src/websocket.ts to retain the request's IncomingMessage in waiterMap and leave waitForWebSocket pending because ws.handleUpgrade emits no connection event. The aborted handshake therefore has no cleanup path, allowing an unauthenticated attacker to flood a public route, cause unbounded memory growth, and eventually make the service unavailable. This issue is fixed in version 2.0.10.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @hono/node-server | 2.0.10 | GHSA-9mqv-5hh9-4cgg |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| honojs | node-server | >= 2.0.0, < 2.0.10 |
Weakness: CWE-401, CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L