CVE-2020-26953

MediumCVSS 4.3/10Last modified Jun 17, 2026

Description

It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Metrics

CVSS 3.1 4.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Weakness enumeration

CWE-1021

Affected software

No affected versions have been published.

Timeline

Published: Dec 9, 2020
Last modified: Jun 17, 2026
NVD status: Modified

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