CVE-2026-4716: Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component

Published Mar 24, 2026
·
Updated

Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.

Other sources

Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

MITRE

Affected Software

8 affected componentsFixes available
Mozilla Firefox<149
Mozilla Firefox ESR<140.9
Mozilla Firefox<149
149
Mozilla Firefox ESR<140.9
140.9
Mozilla Firefox<140.9.0
Mozilla Firefox<149.0
Mozilla Thunderbird<140.9
140.9
Mozilla Thunderbird<149
149

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 Red Hat·01:02 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·01:16 PM
DescriptionSeverityWeaknessAffected Software
Apr 7, 58249
Event
via FIRST·05:17 PM

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2026-4716?

CVE-2026-4716 has a high severity due to the potential for exploitation through uninitialized memory in the JavaScript Engine component.

2

How do I fix CVE-2026-4716?

To fix CVE-2026-4716, update Firefox to version 149 or later, or Firefox ESR to version 140.9 or later.

3

What versions of Firefox are affected by CVE-2026-4716?

CVE-2026-4716 affects Firefox versions earlier than 149 and Firefox ESR versions earlier than 140.9.

4

What component is impacted by CVE-2026-4716?

CVE-2026-4716 impacts the JavaScript Engine component in the affected versions of Firefox.

5

Can CVE-2026-4716 lead to data compromise?

Yes, CVE-2026-4716 can potentially lead to data compromise due to incorrect boundary conditions and uninitialized memory.

Contact

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