CVE-2026-2787: Use-after-free in the DOM: Window and Location component

Published Feb 24, 2026
·
Updated

Use-after-free in the DOM: Window and Location component. This vulnerability affects Firefox < 148, Firefox ESR < 115.33, and Firefox ESR < 140.8.

Other sources

Use-after-free in the DOM: Window and Location component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

— MITRE

Affected Software

10 affected componentsFixes available
Mozilla Firefox<148
148
Mozilla Firefox ESR<140.8
140.8
Mozilla Firefox ESR<115.33
115.33
Mozilla Thunderbird<148
148
Mozilla Thunderbird<140.8
140.8
Mozilla Firefox<115.33.0
Mozilla Firefox<148.0
Mozilla Firefox>=128.0<140.8.0
Mozilla Thunderbird<140.8.0
Mozilla Thunderbird<148.0

Event History

Feb 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·01:33 PM
Data Sourced
via MITRE·01:33 PM
Description
Data Sourced
via Red Hat·02:03 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:16 PM
DescriptionSeverityWeaknessAffected Software
Jan 4, 58137
Event
via FIRST·01:30 PM

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is the severity of CVE-2026-2787?

CVE-2026-2787 has a critical severity rating of 9.8 according to CVSS 3.1.

2

Which software versions are affected by CVE-2026-2787?

CVE-2026-2787 affects Firefox versions earlier than 148, Firefox ESR versions earlier than 115.33, and Firefox ESR versions earlier than 140.8.

3

How do I fix CVE-2026-2787?

To mitigate CVE-2026-2787, update to Firefox version 148 or later, Firefox ESR version 115.33 or later, or Firefox ESR version 140.8 or later.

4

What type of vulnerability is CVE-2026-2787 classified as?

CVE-2026-2787 is classified as a Use-After-Free vulnerability.

5

What components are primarily affected by CVE-2026-2787?

CVE-2026-2787 primarily affects the Window and Location components of the DOM.

Company

Resources

Contact

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