# CVE-2020-26954: Firefox ESR and 1 other: When accepting a malicious intent from other installed apps, Firefox for Android accepted manifests from…

CVE-2020-26954 is fixed in Mozilla Firefox ESR (en-US) on 1 platform by Mozilla Firefox ESR (en-US) 91.0 (version 91.0), released August 4, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-26954
- Priority: Routine
- CVSS: 4.3
- EPSS: 0.0064
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 9, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-26954

## 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 only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 83.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox ESR (en-US) | 91.0 | [Mozilla Firefox ESR (en-US) 91.0](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-91.0.md) | Aug 4, 2021 |

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