CVE-2026-74937: Use-after-free in the JavaScript: GC component

Published Aug 18, 2026
·
Updated

Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 154 and Firefox ESR 153.1.

Affected Software

3 affected componentsFixes available
Mozilla Firefox>154<154
Mozilla Firefox<154
154
Mozilla Firefox ESR<153.1
153.1

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 154
  2. Upgrade

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

    Fixed in 153.1
  3. Upgrade

    Upgrade Mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 154
  4. Upgrade

    Upgrade Mozilla Firefox ESR to a version that resolves this vulnerability.

    Fixed in 153.1

Event History

Aug 18, 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·12:23 PM
Data Sourced
via MITRE·12:23 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

Which Firefox releases include the fix?

Firefox 154 and Firefox ESR 153.1 contain the fix. The provided information does not identify earlier affected version ranges or any affected configuration details.

2

What exploitation prerequisites or mitigations are documented?

The issue is a use-after-free in Firefox's JavaScript garbage-collection component. The provided information does not state the attacker prerequisites, exploitation method, or any temporary mitigation for unpatched installations.

Contact

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