# CVE-2026-126343: @hono/node-server: Unhandled `ECONNRESET` on the socket during an asynchronous WebSocket upgrade crashes the process

Status: published. Published: 2026-11-12. Updated: 2026-11-13.

@hono/node-server allows running the Hono application on Node.js. From 2.0.0 until 2.1.6, the WebSocket upgrade handler waits for the Hono application to finish asynchronous middleware or handler work without first attaching an error listener to the socket. If an unauthenticated client resets the TCP connection during that window, the socket emits an unhandled ECONNRESET error and terminates the Node.js process. If a global uncaughtException handler suppresses termination, the pending upgrade waiter is not released and repeated requests can grow the heap. This affects applications that enable WebSocket support and perform asynchronous work on the upgrade path. This issue is fixed in version 2.1.6.

## Remediation

- fix: @hono/node-server (npm): OSV reports a fixed version 2.1.6. Check the advisory for supported release branches. (source: OSV GHSA-qv5m-9pm6-hqp3) — https://github.com/advisories/GHSA-qv5m-9pm6-hqp3

## Affected products and versions

- honojs / node-server: >= 2.0.0, < 2.1.6 (affected). Source: CNA: GitHub_M
-  / @hono/node-server (@hono/node-server): ≥ 2.0.0; < 2.1.6 (affected, semver); OSV events: introduced 2.0.0; fixed 2.1.6. Source: OSV GHSA-qv5m-9pm6-hqp3

## Severity and prioritization

- CVSS 3.1: 5.3 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L; source: CNA: GitHub_M

- CVSS 3.1: 5.3 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L; source: NVD: security-advisories@github.com

- CISA KEV: No listing in collected sources

- EPSS: 0.45% as of 2026-11-13; percentile 39.87%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-248

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/honojs/node-server/security/advisories/GHSA-qv5m-9pm6-hqp3 (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/honojs/node-server/commit/61cc0267e613e684401f17c27538ba3bf97339a4 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/honojs/node-server/releases/tag/v2.1.6 (CNA: GitHub_M; x_refsource_MISC)

- https://github.com/honojs/node-server/commit/61cc0267e613e684401f17c27538ba3bf97339a4 (security-advisories@github.com)

- https://github.com/honojs/node-server/releases/tag/v2.1.6 (security-advisories@github.com)

- https://github.com/honojs/node-server/security/advisories/GHSA-qv5m-9pm6-hqp3 (security-advisories@github.com)

- https://github.com/advisories/GHSA-qv5m-9pm6-hqp3 (OSV / GitHub Security Advisories; advisory)

- https://osv.dev/vulnerability/GHSA-qv5m-9pm6-hqp3 (OSV / GitHub Security Advisories; osv)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2026-126343; retrieved 2026-11-13; source updated 2026-11-13

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-126343; retrieved 2026-11-13; source updated 2026-11-12

- OSV / GitHub Security Advisories: https://osv.dev/vulnerability/GHSA-qv5m-9pm6-hqp3; retrieved 2026-11-12; source updated 2026-11-12

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-126343; retrieved 2026-11-13; source updated Not reported

Revision: 43bb671c7ed2298070543f00825f3be115ca1ca41795b77098837bd79ab80a13

Canonical: https://y2.dev/cve/CVE-2026-126343

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