CVE-2026-8389: JIT miscompilation in the JavaScript Engine: JIT component

Published May 12, 2026
·
Updated

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 150.0.3.

Affected Software

3 affected componentsFixes available
Mozilla Firefox<150.0.3
Mozilla Firefox<150.0.3
150.0.3
Mozilla Firefox<150.0.3

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 150.0.3
  2. Upgrade

    Upgrade Mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 150.0.3

Event History

May 12, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·12:36 PM
Data Sourced
via MITRE·12:36 PM
Description
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:17 PM
DescriptionSeverityWeaknessAffected Software

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-2026-8389?

CVE-2026-8389 has been classified as a moderate severity vulnerability due to the potential for JIT miscompilation in the JavaScript Engine.

2

How do I fix CVE-2026-8389?

To fix CVE-2026-8389, update your Firefox browser to version 150.0.3 or later.

3

What does CVE-2026-8389 affect?

CVE-2026-8389 affects the JIT component of the JavaScript Engine within Firefox prior to version 150.0.3.

4

Is there a workaround for CVE-2026-8389?

There are no official workarounds available for CVE-2026-8389, so upgrading to the patched version is recommended.

5

When was CVE-2026-8389 discovered?

CVE-2026-8389 was disclosed in the cybersecurity advisory released by Mozilla.

Company

Resources

Contact

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