CVE-2026-100793: JIT miscompilation in the JavaScript Engine component

Published Sep 29, 2026
·
Updated

JIT miscompilation in the JavaScript Engine component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<157
157
Mozilla Thunderbird<157
157

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 157
  2. Upgrade

    Upgrade Mozilla Thunderbird to a version that resolves this vulnerability.

    Fixed in 157
  3. Upgrade

    Upgrade Mozilla Firefox to a version that resolves this vulnerability.

    Fixed in 157

Event History

Sep 29, 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 NVD·01:17 PM
DescriptionSeverityWeakness
Sep 30, 2026
Updated
via Mozilla·12:00 AM
Affected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What update should be applied to address this issue?

Update Mozilla Firefox to version 157, which includes the fix for this vulnerability.

Company

Resources

Contact

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