5.4
MEDIUM CVSS 3.1
CVE-2026-126344
@hono/node-server: WebSocket upgrade request-target starting with `//` replaces the host in `c.req.url`, bypassing `Origin` checks
Description

@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.

INFO

Published Date :

Nov. 12, 2026, 10:19 p.m.

Last Modified :

Nov. 12, 2026, 10:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-126344 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Hono node-server
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM MITRE-CVE
CVSS 3.1 MEDIUM [email protected]
Solution
Update @hono/node-server to version 2.1.6 to fix WebSocket origin verification.
  • Update @hono/node-server to version 2.1.6.
  • Verify WebSocket origin checks.
  • Review Host header handling for security.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-126344.

URL Resource
https://github.com/honojs/node-server/commit/cfaa79f76dbb0fe9f539438c0c585d94ed7cd01f
https://github.com/honojs/node-server/releases/tag/v2.1.6
https://github.com/honojs/node-server/security/advisories/GHSA-7v5p-43qr-wch5
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-126344 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-126344 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-126344 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-126344 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Nov. 12, 2026

    Action Type Old Value New Value
    Added Description @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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
    Added CWE CWE-1385
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/126xxx/CVE-2026-126344.json">CVE-2026-126344</a>
    Added Reference https://github.com/honojs/node-server/commit/cfaa79f76dbb0fe9f539438c0c585d94ed7cd01f
    Added Reference https://github.com/honojs/node-server/releases/tag/v2.1.6
    Added Reference https://github.com/honojs/node-server/security/advisories/GHSA-7v5p-43qr-wch5
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.