---
id: CVE-2026-109714
title: Incorrect boundary conditions in the Layout component
summary: >-
  Incorrect boundary conditions in the Layout component. This vulnerability was
  fixed in Firefox 158 and Thunderbird 158.
severity: medium
cvss: 5.4
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N'
cwe:
  - CWE-119
  - CWE-193
vendor: Mozilla
product: Firefox
affected:
  - Firefox
  - Thunderbird
published: '2026-10-13'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T20:17:07.330'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109714'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2069765'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-106/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-109/'
    label: security@mozilla.org
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109714.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-109714'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2550398'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-109714'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109714'
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-106/#CVE-2026-109714'
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-109/#CVE-2026-109714'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.0021
epssPercentile: 0.11164
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-15T19:53:14.814371Z'
scores:
  nvd: 5.4
  adp: 5.4
  vendor: 7.5
ingestedAt: '2026-10-13T13:27:03.993Z'
---

## Overview

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

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Important · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-109714.json)