Answer in brief
CVE-2026-126344 records a Medium severity (CVSS 5.4) vulnerability in @hono/node-server: WebSocket upgrade request-target starting with `//` replaces the host in `c.req.url`, bypassing `Origin` checks. The current sources do not mark it as known exploited. The current feed maps honojs/node-server (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.4. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps honojs/node-server (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| honojs/node-servergeneric | >=2.0.0 <2.1.6 | 2.1.6 |
Published upstream
Nov 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 12, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 12, 2026
@hono/node-server allows running the Hono application on Node.js. From 2.0.0 until 2.1.6, the WebSocket upgrade path resolves a raw request-target beginning with // against a base URL built from the Host header, causing the WHATWG URL parser to treat the request-target as a network-path reference and replace the host in c.req.url. Routing still uses the local WebSocket path, so an application that compares the Origin header with the origin of c.req.url, including checks implemented with csrf(), compares an attacker's origin with itself and accepts the connection. A page on another site can consequently open a WebSocket with the victim's cookies and read and send messages when the application uses upgradeWebSocket and trusts the host in c.req.url. Ordinary HTTP requests are not affected. This issue is fixed in version 2.1.6.
Quoted source text, attributed separately from HOL analysis.