CVE-2026-124863: Use-after-free in the DOM: HTML Parser component

Published Nov 10, 2026
·
Updated

Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 160, Firefox ESR 115.45, and Firefox ESR 153.7.

Affected Software

5 affected componentsFixes available
Mozilla Firefox<160
Mozilla Firefox ESR<115.45, <153.7
Mozilla Firefox ESR<115.45
115.45
Mozilla Firefox ESR<153.7
153.7
Mozilla Firefox<160
160

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 115.45
  2. Upgrade

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

    Fixed in 153.7
  3. Upgrade

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

    Fixed in 160
  4. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 160
  5. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.45
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 153.7

Event History

Nov 10, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·01:28 PM
Data Sourced
via MITRE·01:28 PM
Description
Data Sourced
via NVD·02:17 PM
DescriptionSeverityWeakness

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

Which Firefox releases contain the fix?

The issue was fixed in Firefox 160, Firefox ESR 115.45, and Firefox ESR 153.7.

2

Does exploitation require local access or existing privileges?

No. The vector is network-based and the vulnerability does not require privileges, although user interaction is required.

Company

Resources

Contact

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