CVE-2021-23976

HighCVSS 8.1/10Last modified Jun 17, 2026

Description

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 is a different issue from CVE-2020-26954 and only affected Firefox for Android. Other operating systems are unaffected. This vulnerability affects Firefox < 86.

Metrics

CVSS 3.1 8.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Weakness enumeration

CWE-1021

Affected software

No affected versions have been published.

Timeline

Published: Feb 26, 2021
Last modified: Jun 17, 2026
NVD status: Modified

Related CVEs from 2021

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