CVE-2026-4727: Denial-of-service in the Libraries component in NSS

Published Mar 24, 2026
·
Updated

Denial-of-service in the Libraries component in NSS. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

Affected Software

5 affected componentsFixes available
Mozilla Firefox<149
Mozilla Firefox<149
149
Mozilla Thunderbird<149
149
Mozilla Firefox<149.0
Mozilla Thunderbird<149.0

Event History

Mar 24, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
CVE Published
via MITRE·12:30 PM
Data Sourced
via MITRE·12:30 PM
Description
Data Sourced
via NVD·01:16 PM
DescriptionSeverityWeaknessAffected Software
Apr 7, 58249
Event
via FIRST·05:33 PM

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2026-4727?

CVE-2026-4727 is classified as a denial-of-service vulnerability affecting Firefox versions prior to 149.

2

How does CVE-2026-4727 affect users?

CVE-2026-4727 can cause a denial-of-service condition, making the affected version of Firefox unresponsive.

3

How can I fix CVE-2026-4727?

To fix CVE-2026-4727, users should update to Firefox version 149 or later.

4

What components are affected by CVE-2026-4727?

CVE-2026-4727 affects the Libraries component in NSS within Firefox.

5

Is there a workaround for CVE-2026-4727?

There are no specific workarounds recommended for CVE-2026-4727 other than updating the software.

Company

Resources

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