CVE-2026-6779: Other issue in the JavaScript Engine component

Published Apr 21, 2026
·
Updated

Other issue in the JavaScript Engine component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Affected Software

4 affected componentsFixes available
Mozilla Firefox<150
150
Mozilla Thunderbird<150
150
Mozilla Firefox<150.0
Mozilla Thunderbird<150.0

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
  2. Upgrade

    Upgrade Firefox (JavaScript Engine) to a version that resolves this vulnerability.

    Fixed in 150
  3. Upgrade

    Upgrade Thunderbird (JavaScript Engine) to a version that resolves this vulnerability.

    Fixed in 150

Event History

Apr 21, 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·12:41 PM
Data Sourced
via MITRE·12:41 PM
Description
Data Sourced
via NVD·01:16 PM
DescriptionSeverityWeaknessAffected Software
May 21, 58279
Event
via FIRST·08:08 AM

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2026-6779?

The severity level of CVE-2026-6779 is classified as high due to its potential to allow arbitrary code execution.

2

How do I fix CVE-2026-6779?

To fix CVE-2026-6779, users should update to Firefox or Thunderbird version 150 or later.

3

What products are affected by CVE-2026-6779?

CVE-2026-6779 affects Mozilla Firefox versions below 150 and Mozilla Thunderbird versions below 150.

4

What type of vulnerability is CVE-2026-6779?

CVE-2026-6779 is classified as an issue in the JavaScript Engine component.

5

When was CVE-2026-6779 fixed?

CVE-2026-6779 was fixed in version 150 of Firefox and Thunderbird.

Contact

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