CVE-2026-118007: Use-after-free in the JavaScript: GC component

Published Oct 27, 2026
·
Updated

Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 159.

Affected Software

1 affected componentFixes available
Mozilla Firefox<159
159

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 159
  2. Upgrade

    Upgrade Mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 159

Event History

Oct 27, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·02:05 PM
Data Sourced
via MITRE·02:05 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

Which Firefox versions are affected?

The provided information states that the issue was fixed in Firefox 159. It does not identify the first affected version or affected release channels.

2

What must an attacker do to exploit this issue?

The provided information identifies a use-after-free in Firefox's JavaScript garbage-collection component, but does not specify the delivery method, user interaction requirements, or other exploitation prerequisites.

3

How can I determine whether my installation is protected?

Check whether the installed Firefox version includes Firefox 159 or the vendor's fix for this issue. The provided information does not include detection indicators or evidence that would show prior exploitation.

Company

Resources

Contact

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