CVE-2026-109753: Incorrect boundary conditions in the Layout component

Published Oct 13, 2026
·
Updated

Incorrect boundary conditions in the Layout component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, and Firefox ESR 153.5.

Other sources

Incorrect boundary conditions in the Layout component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

— NVD

Affected Software

5 affected componentsFixes available
Mozilla Firefox<158
158
Mozilla Firefox ESR<115.43
115.43
Mozilla Firefox ESR<153.5
153.5
Mozilla Thunderbird<153.5
153.5
Mozilla Thunderbird<158
158

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 158
  2. Upgrade

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

    Fixed in 115.43
  3. Upgrade

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

    Fixed in 153.5
  4. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 158
  5. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 115.43
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 153.5
  7. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 158
  8. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 153.5

Event History

Oct 13, 2026
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
CVE Published
via MITRE·12:29 PM
Data Sourced
via MITRE·12:29 PM
Description
Data Sourced
via NVD·01:17 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 158, Firefox ESR 115.43, and Firefox ESR 153.5.

Company

Resources

Contact

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