---
id: CVE-2026-109742
title: Information disclosure in the PDF Viewer component
summary: >-
  Information disclosure in the PDF Viewer component. This vulnerability was
  fixed in Firefox 158 and Firefox ESR 153.5.
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N'
cwe:
  - CWE-200
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T16:19:16.897'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109742'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2058800'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-106/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-108/'
    label: security@mozilla.org
tags:
  - nvd
ingestedAt: '2026-10-13T13:27:04.004Z'
---

## Overview

Information disclosure in the PDF Viewer component. This vulnerability was fixed in Firefox 158 and Firefox ESR 153.5.

## Remediation

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