---
id: CVE-2020-26955
title: >-
  When a user downloaded a file in Firefox for Android, if a cookie is set, it
  would have been re-sent during a subsequent file download operation on the
  same domain, regardless of whether the original and subsequent request were in
  privat…
summary: >-
  When a user downloaded a file in Firefox for Android, if a cookie is set, it
  would have been re-sent during a subsequent file download operation on the
  same domain, regardless of whether the original and subsequent request were in
  privat…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N'
cwe:
  - CWE-565
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-2020-26955'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=1663261'
    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=1663261'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.mozilla.org/security/advisories/mfsa2020-50/'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00826
epssPercentile: 0.55557
ingestedAt: '2026-08-19T15:41:15.012Z'
---

## Overview

When a user downloaded a file in Firefox for Android, if a cookie is set, it would have been re-sent during a subsequent file download operation on the same domain, regardless of whether the original and subsequent request were in private and non-private browsing modes. *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`