---
id: CVE-2020-26954
title: >-
  When accepting a malicious intent from other installed apps, Firefox for
  Android accepted manifests from arbitrary file paths and allowed declaring
  webapp manifests for other origins
summary: >-
  When accepting a malicious intent from other installed apps, Firefox for
  Android accepted manifests from arbitrary file paths and allowed declaring
  webapp manifests for other origins. This could be used to gain fullscreen
  access for UI s…
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N'
vendor: mozilla
product: firefox_mobile
affected:
  - firefox_mobile < 83.0
patched:
  - firefox_mobile 83.0
published: '2020-12-09'
updated: '2026-08-19'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2020-26954'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=1657026'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2020-50/'
    label: security@mozilla.org
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=1657026'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.mozilla.org/security/advisories/mfsa2020-50/'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00643
epssPercentile: 0.48739
ingestedAt: '2026-08-19T15:41:14.807Z'
---

## Overview

When accepting a malicious intent from other installed apps, Firefox for Android accepted manifests from arbitrary file paths and allowed declaring webapp manifests for other origins. This could be used to gain fullscreen access for UI spoofing and could also lead to cross-origin attacks on targeted websites. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 83.

## Affected

- `firefox_mobile < 83.0`

## Remediation

Upgrade past the affected range:

- `firefox_mobile 83.0`