vulnerability
MFSA2020-51 Firefox: Security Vulnerabilities fixed in Firefox ESR 78.5 (CVE-2020-26953)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Nov 17, 2020 | Nov 18, 2020 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Nov 17, 2020
Added
Nov 18, 2020
Modified
Mar 27, 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.
Solution
mozilla-firefox-esr-upgrade-78_5
Rapid7 Labs
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