UBUNTU-CVE-2026-124871: Use After Free

Published Nov 12, 2026

Updated

Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 160 and Thunderbird 160.

Affected Software

10 affected components

ubuntu/mozjs52*

ubuntu/mozjs38*

ubuntu/mozjs68*

ubuntu/mozjs52*

ubuntu/mozjs102*

ubuntu/mozjs78*

ubuntu/mozjs91*

ubuntu/thunderbird*

ubuntu/mozjs102*

ubuntu/mozjs115*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade Firefox to a version that resolves this vulnerability.
Fixed in 160
Upgrade
Upgrade Thunderbird to a version that resolves this vulnerability.
Fixed in 160

Event History

Nov 12, 2026

CVE Published

via OSV·12:00 AM

Data Sourced

via OSV·12:00 AM

DescriptionSeverityAffected Software

Frequently Asked Questions

Which products are confirmed to contain the fix?

The vulnerability was fixed in Firefox 160 and Thunderbird 160. The listed Ubuntu software includes Thunderbird and multiple mozjs packages, but the provided data does not specify package-level fixed versions.

How can I determine whether an affected Ubuntu package has been updated?

Check the installed package version against the fixed version published in Ubuntu's security advisory for this CVE. The provided information identifies the affected package names but does not include their patched Ubuntu version numbers.