CVE-2026-45736

Description

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.

Overview

State: PUBLISHED
Assigner (CNA): GitHub_M
CVSS severity: MEDIUM
CVSS score: 4.4 / 10
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
Effective score: 4.4 / 10 MEDIUM source: CNA overview
MSRC score: 4.4 / 10 MEDIUM MS rating: Moderate
CWE(s): CWE-908
Reserved: 2026-05-13
Published: 2026-05-15 16:53 UTC
Last updated: 2026-05-16 03:09 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/45xxx/CVE-2026-45736.json
Linked Threat: CVE-2026-45736 — CVE-2026-45736

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-05-15 15:16:54 UTC
NVD last modified: 2026-05-19 14:39:20 UTC
NVD CVSS v3.1: 4.4 / 10 MEDIUM source: security-advisories@github.com
NVD CVSS vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
Exploitability subscore: 0.7 / 10
Impact subscore: 3.6 / 10
EPSS score: 0.0001 (probability of exploitation in next 30 days)
EPSS percentile: 1.85% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-30543
Assigner: GitHub_M
Published: May 15, 2026, 2:53:57 PM
Updated: May 16, 2026, 1:09:15 AM
EUVD base score (CVSS 3.1): 4.4 / 10
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
EUVD-reported EPSS: 0.0100
Vendors: websockets
Products: ws (8.0.0, < 8.20.1)
Aliases: GHSA-58qx-3vcg-4xpx

ENISA description: 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.

EUVD references (2)

Microsoft Security Response Center MSRC

Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-07-28 03:00 UTC (source: CVRF).

MS severity: Moderate
MS CVSS base score: 4.4 / 10 (temporal 4.4)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
Release: 2026-May

Affected products (1)

Vendor	Product	Versions	Platforms
websockets	ws	`>= 8.0.0, < 8.20.1` (affected)	—

Affected products — CPE 2.3 (1) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:ws_project:ws:*:*:*:*:*:node.js:*:*

Vendor references (2)

References embedded in the original CVE record by the assigning CNA.

https://github.com/websockets/ws/security/advisories/GHSA-58qx-3vcg-4xpx x_refsource_CONFIRM
https://github.com/websockets/ws/commit/c0327ec15a54d701eb6ccefaa8bef328cfc03086 x_refsource_MISC

MITRE references (2) cveawg.mitre.org

Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.

https://github.com/websockets/ws/commit/c0327ec15a54d701eb6ccefaa8bef328cfc03086 x_refsource_MISC
https://github.com/websockets/ws/security/advisories/GHSA-58qx-3vcg-4xpx x_refsource_CONFIRM

Web references (4)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

MSRC update guide: CVE-2026-45736 msrc
https://nvd.nist.gov/vuln/detail/CVE-2026-45736 tenable:nvd.nist.gov
https://www.cve.org/CVERecord?id=CVE-2026-45736 tenable:www.cve.org
https://www.first.org/epss/ tenable:www.first.org

NVD-tagged references (3)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/websockets/ws/commit/c0327ec15a54d701eb6ccefaa8bef328cfc03086 security-advisories@github.com Patch
https://github.com/websockets/ws/security/advisories/GHSA-58qx-3vcg-4xpx security-advisories@github.com ExploitPatchVendor Advisory
https://github.com/websockets/ws/security/advisories/GHSA-58qx-3vcg-4xpx 134c704f-9b21-4f2e-91b3-4a467353bcc0 ExploitPatchVendor Advisory

Remediations (14)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

ws: Uninitialized memory disclosure · CVE-2026-45736 - GitHub

web:github.com

Impact The websocket.close () implementation is vulnerable to uninitialized memory disclosure when a TypedArray is passed as the reason argument.

2026-05-23 20:51 UTC
Security Update Guide - Microsoft Security Response Center

web:msrc.microsoft.com

Security Update Guide - Microsoft Security Response Center

2026-05-23 20:51 UTC
Oracle CPU April 2026: Delayed RUs & First Analysis

web:oradba.ch

19c 26ai cve oracle-cpu patch -management release-update security Oracle CPU April 2026 : Delayed RUs & First Analysis On April 21, 2026 , Oracle released the Critical Patch Update (CPU) for April 2026 — 481 new security fixes across the entire Oracle product stack. For Oracle Database, this means another round of mandatory patching.

2026-05-23 20:51 UTC
CVE-2026-45736 - security-tracker.debian.org

web:security-tracker.debian.org

Vulnerable and fixed packages The table below lists information on source packages.

2026-05-23 20:51 UTC
SAP Security Patch Day - March 2026

web:support.sap.com

SAP security patch day bulletin

2026-05-23 20:51 UTC
Critical Patches Issued for Microsoft Products, April 14, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-05-23 20:51 UTC
Oracle Critical Patch Update Advisory - April 2026

web:www.oracle.com

This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.

2026-05-23 20:51 UTC
CVE-2026-45736: Uninitialized Memory Disclosure vulnerability in ws (npm)

web:www.resolvedsecurity.com

What is CVE-2026-45736 About? This uninitialized memory disclosure vulnerability in `websocket.close ()` in `ws` allows for the disclosure of uninitialized memory when a `TypedArray` is passed as the `reason` argument. This flaw can lead to information disclosure. Exploitation requires specific misuse of the websocket `close` method, making it unlikely in typical scenarios.

2026-05-23 20:51 UTC
Windows 11 April 2026 Update tested: What's new, improved and fixed

web:www.windowslatest.com

Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.

2026-05-23 20:51 UTC
Patch Tuesday May 2026: Security Updates & CVE Analysis

web:zecurit.com

Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .

2026-05-23 20:51 UTC
Security Advisories and Bulletins | Microsoft Learn

web:learn.microsoft.com

In this library you will find the following security documents that have been released by the Microsoft Security Response Center (MSRC). The MSRC investigates all reports of security vulnerabilities affecting Microsoft products and services, and releases these documents as part of the ongoing effort to help you manage security risks and help keep your systems protected. Please use the ...

2026-05-26 02:55 UTC
Oracle Critical Patch Update, April 2026 Security Update Review

web:threatprotect.qualys.com

Oracle released its second quarterly edition of this year's Critical Patch Update. The update received patches for 481 security vulnerabilities. Some of the vulnerabilities addressed in this update impact more than one product. These patches address vulnerabilities in various product families, including third-party components in Oracle products.

2026-05-26 02:55 UTC
Microsoft April 2026 Patch Tuesday fixes 167 flaws, 2 zero-days

web:www.bleepingcomputer.com

Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.

2026-05-26 02:55 UTC
Windows 11 KB5083769 April 2026 update triggers death loops and BSODs

web:www.notebookcheck.net

Microsoft's Windows 11 KB5083769 April 2026 update causes critical boot failures, pixelated BSODs, and BitLocker recovery loops on Windows 11 24H2 and 25H2 PCs.

2026-05-26 02:55 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-45736.json.

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