CVE-2026-117869: Use-after-free in the DOM: Core & HTML component

Published Oct 27, 2026
·
Updated

Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6.

Affected Software

3 affected componentsFixes available
Mozilla Firefox ESR<115.44
115.44
Mozilla Firefox ESR<153.6
153.6
Mozilla Firefox<159
159

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 115.44
  2. Upgrade

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

    Fixed in 153.6
  3. Upgrade

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

    Fixed in 159
  4. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 159
  5. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.44
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 153.6

Event History

Oct 27, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·02:05 PM
Data Sourced
via MITRE·02:05 PM
Description

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 159, Firefox ESR 115.44, and Firefox ESR 153.6.

2

Which products should be checked for exposure?

Mozilla Firefox and Mozilla Firefox ESR should be checked. Versions earlier than the listed fixed releases may be affected based on the available information.

Company

Resources

Contact

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