CyberSecBulletin
CVE-2026-45736NVD status: Modified

ws: Use of Uninitialized Resource

Published Updated By the CyberSecBulletin desk

CVE-2026-45736 is a high-severity use of uninitialized resource vulnerability in ws from Websockets, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected ws versions: >= 8.0.0, < 8.20.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.74% chance of exploitation within 30 days, higher than 55% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of ws you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Websocketsws>= 8.0.0, < 8.20.1Not stated
Red HatCryostat 4 on RHEL 9Not specified in the recordNot stated
Red HatRed Hat AMQ Broker 7.13.6Not specified in the recordNot stated
Red HatRed Hat AMQ Broker 7.14.1Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 10Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.6Not specified in the recordNot stated
Red HatRed Hat Developer Hub 1.10Not specified in the recordNot stated
Red HatRed Hat Developer Hub 1.9Not specified in the recordNot stated
Red HatRed Hat Discovery 2Not specified in the recordNot stated
Red HatRed Hat Hardened ImagesNot specified in the recordNot stated
Red HatRed Hat Migration Toolkit 1.8Not specified in the recordNot stated
Red HatRed Hat OpenShift AI 2.25Not specified in the recordNot stated
Red HatRed Hat OpenShift AI 3.4Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.19Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.20Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.21Not specified in the recordNot stated
Red HatRed Hat OpenShift Container Platform 4.22Not specified in the recordNot stated
Red HatRed Hat Openshift Data Foundation 4.18Not specified in the recordNot stated
Red HatRed Hat Openshift Data Foundation 4.19Not specified in the recordNot stated
Red HatRed Hat Openshift Data Foundation 4.20Not specified in the recordNot stated
Red HatRed Hat Openshift Data Foundation 4.22Not specified in the recordNot stated
Red HatRed Hat OpenShift Dev Spaces 3.29Not specified in the recordNot stated
Red HatRed Hat Trusted Artifact Signer 1.4Not specified in the recordNot stated
Red HatCryostat 4Not specified in the recordNot stated
Red HatGatekeeper 3Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 25 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.14.4MediumCNA (github.com)
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCNA

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Uninitialized Resource

The product uses or accesses a resource that has not been initialized.

How developers prevent this class of flaw

  • Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
  • Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
  • Avoid race conditions (CWE-362) during initialization routines.

More Use of Uninitialized Resource vulnerabilities (CWE-908)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in ws

All ws vulnerabilities

Recent Use of Uninitialized Resource vulnerabilities

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