REDHAT-BUG-2489661: High severity npm/ws vulnerability

Published Jun 16, 2026
·
Updated

ws is an open source WebSocket client and server for Node.js. All versions from 1.1.0 up to (but not including) 5.2.5, from 6.0.0 up to 6.2.4, from 7.0.0 up to 7.5.11, and from 8.0.0 up to 8.21.0 are affected by a memory exhaustion DoS vulnerability. A peer can send a high volume of exceptionally small fragments and data chunks, with modest network traffic, to force the remote peer into allocating and holding structural wrappers that consume far more memory than the default documented message-size limit, leading to process termination due to OOM. This issue has been fixed in versions 5.2.5, 6.2.4, 7.5.11, and 8.21.0.

Affected Software

1 affected component
npm/ws>1.1.0<5.2.5, >6.0.0<6.2.4, >7.0.0<7.5.11, >8.0.0<8.21.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade ws to a version that resolves this vulnerability.

    Fixed in 5.2.5
  2. Upgrade

    Upgrade ws to a version that resolves this vulnerability.

    Fixed in 6.2.4
  3. Upgrade

    Upgrade ws to a version that resolves this vulnerability.

    Fixed in 7.5.11
  4. Upgrade

    Upgrade ws to a version that resolves this vulnerability.

    Fixed in 8.21.0

Event History

Jun 16, 2026
Data Sourced
via Red Hat·10:01 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2489661?

The severity of REDHAT-BUG-2489661 is rated as high with a score of 7.

2

How do I fix REDHAT-BUG-2489661?

To fix REDHAT-BUG-2489661, you need to upgrade the ws library to a version that is not affected by the vulnerability, specifically to versions 5.2.5, 6.2.4, 7.5.11, or 8.21.0 and above.

3

What is the impact of REDHAT-BUG-2489661?

The impact of REDHAT-BUG-2489661 is a memory exhaustion denial-of-service (DoS) vulnerability that could allow a peer to incapacitate the service.

4

Which versions of ws are affected by REDHAT-BUG-2489661?

Versions of ws affected by REDHAT-BUG-2489661 include all versions from 1.1.0 up to (but not including) 5.2.5, from 6.0.0 up to 6.2.4, from 7.0.0 up to 7.5.11, and from 8.0.0 up to 8.21.0.

5

When was REDHAT-BUG-2489661 published?

REDHAT-BUG-2489661 was published on June 16, 2026.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203