What’s Vulnerable › Vulnerabilities

CVE-2026-45736: ws: Uninitialized memory disclosure

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-05-15 · updated 2026-10-26
• Weakness: CWE-908

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.

Affected products

• websockets ws: from 8.0.0 before 8.20.1 — fixed in 8.20.1

How to fix

Upgrade to a fixed version: websockets ws 8.20.1. Check the vendor advisory for mitigations.

References

• https://github.com/websockets/ws/commit/c0327ec15a54d701eb6ccefaa8bef328cfc03086
• https://github.com/websockets/ws/security/advisories/GHSA-58qx-3vcg-4xpx
• https://access.redhat.com/errata/RHSA-2026:26638
• https://access.redhat.com/errata/RHSA-2026:26994
• https://access.redhat.com/errata/RHSA-2026:27171
• https://access.redhat.com/errata/RHSA-2026:29197
• https://access.redhat.com/errata/RHSA-2026:33574
• https://access.redhat.com/errata/RHSA-2026:34374
• https://access.redhat.com/errata/RHSA-2026:36754
• https://access.redhat.com/errata/RHSA-2026:36820
• https://access.redhat.com/errata/RHSA-2026:37272
• https://access.redhat.com/errata/RHSA-2026:40768

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