CVE-2026-109746: Mitigation bypass in the DOM: Security component

Published Oct 13, 2026
·
Updated

Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

Affected Software

13 affected componentsFixes available
ubuntu/mozjs52*
ubuntu/mozjs38*
ubuntu/mozjs68*
ubuntu/mozjs52*
ubuntu/mozjs102*
ubuntu/mozjs78*
ubuntu/mozjs91*
ubuntu/thunderbird*
ubuntu/mozjs102*
ubuntu/mozjs115*
debian/firefox
159.0-1
Mozilla Firefox<158
158
Mozilla Thunderbird<158
158

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 159.0-1
  2. Upgrade

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

    Fixed in 158
  3. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 158
  4. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 158

Event History

Oct 13, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Data Sourced
via Ubuntu·12:00 AM
RemedyDescriptionSeverityAffected Software
CVE Published
via MITRE·12:29 PM
Data Sourced
via MITRE·12:29 PM
Description
Data Sourced
via OSV·01:17 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·01:17 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

Which Firefox versions need remediation?

The vulnerability was fixed in Firefox 158. Install Firefox 158 or a later fixed release.

2

What temporary mitigation is available if Firefox cannot be updated immediately?

No temporary mitigation or configuration workaround is provided in the available information. Updating to Firefox 158 is the documented remediation.

Company

Resources

Contact

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