vulnerability
MFSA2021-52 Firefox: Security Vulnerabilities fixed in Firefox 95 (CVE-2021-43538)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Dec 7, 2021 | Dec 8, 2021 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Dec 7, 2021
Added
Dec 8, 2021
Modified
Mar 27, 2026
Description
By misusing a race in our notification code, an attacker could have forcefully hidden the notification for pages that had received full screen and pointer lock access, which could have been used for spoofing attacks. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.
Solution
mozilla-firefox-upgrade-95_0
Rapid7 Labs
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