websockets ws up to 8.20.0 websocket.close Reason uninitialized resource

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in websockets ws up to 8.20.0. This vulnerability affects the function websocket.close. Executing a manipulation of the argument Reason can lead to uninitialized resource. This vulnerability is registered as CVE-2026-45736. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in websockets ws up to 8.20.0 and classified as problematic. This vulnerability affects the function websocket.close. The manipulation of the argument reason with an unknown input leads to a uninitialized resource vulnerability. The CWE definition for the vulnerability is CWE-908. The product uses or accesses a resource that has not been initialized. As an impact it is known to affect confidentiality. CVE summarizes:

ws is an open source WebSocket client and server for Node.js. Prior to 8.20.1, the websocket.close() implementation is vulnerable to uninitialized memory disclosure when a TypedArray is passed as the reason argument. This vulnerability is fixed in 8.20.1.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-45736 since 05/13/2026. The exploitation appears to be difficult. The attack can be initiated remotely. The exploitation requires an enhanced level of successful authentication. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 324001 (Fedora 43 : python-jupytext (2026-31e6b85f4e)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 8.20.1 eliminates this vulnerability. Applying the patch c0327ec15a54d701eb6ccefaa8bef328cfc03086 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (324001), EUVD (EUVD-2026-30543) and CERT Bund (WID-SEC-2026-2118). Once again VulDB remains the best source for vulnerability data.

Affected

  • IBM App Connect Enterprise

Productinfo

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.7

VulDB Base Score: 2.2
VulDB Temp Score: 2.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔒

CNA Base Score: 4.4
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Uninitialized resource
CWE: CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 324001
Nessus Name: Fedora 43 : python-jupytext (2026-31e6b85f4e)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: ws 8.20.1
Patch: c0327ec15a54d701eb6ccefaa8bef328cfc03086

Timelineinfo

05/13/2026 CVE reserved
05/15/2026 +2 days Advisory disclosed
05/15/2026 +0 days VulDB entry created
07/01/2026 +47 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-58qx-3vcg-4xpx
Status: Confirmed

CVE: CVE-2026-45736 (🔒)
GCVE (CVE): GCVE-0-2026-45736
GCVE (VulDB): GCVE-100-364180
EUVD: 🔒
CERT Bund: WID-SEC-2026-2118 - IBM App Connect Enterprise: Mehrere Schwachstellen

Entryinfo

Created: 05/15/2026 18:00
Updated: 07/01/2026 10:56
Changes: 05/15/2026 18:00 (67), 05/16/2026 08:59 (1), 05/21/2026 09:25 (11), 06/29/2026 14:05 (7), 07/01/2026 10:56 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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