honojs node-server up to 2.1.5 WebSocket Upgrade exceptional condition

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00+

Summaryinfo

A vulnerability, which was classified as problematic, was found in honojs node-server up to 2.1.5. This issue affects some unknown processing of the component WebSocket Upgrade Handler. Such manipulation leads to exceptional condition. This vulnerability is referenced as CVE-2026-126343. It is possible to launch the attack remotely. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in honojs node-server up to 2.1.5 and classified as problematic. Affected by this issue is some unknown functionality of the component WebSocket Upgrade Handler. The manipulation with an unknown input leads to a exceptional condition vulnerability. Using CWE to declare the problem leads to CWE-755. The product does not handle or incorrectly handles an exceptional condition. Impacted is availability. CVE summarizes:

@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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-126343 since 11/10/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available.

Upgrading to version 2.1.6 eliminates this vulnerability.

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Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Exceptional condition
CWE: CWE-755
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: node-server 2.1.6

Timelineinfo

11/10/2026 CVE reserved
11/12/2026 +2 days Advisory disclosed
11/12/2026 +0 days VulDB entry created
11/12/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CNA: GitHub_M
CVE: CVE-2026-126343 (🔒)

GCVE (CVE): GCVE-0-2026-126343
GCVE (VulDB): GCVE-100-436550

Entryinfo

Created: 11/12/2026 22:50
Changes: 11/12/2026 22:50 (64)
Complete: 🔍
Cache ID: 216::103

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