vulnerability
MFSA2021-53 Firefox: Security Vulnerabilities fixed in Firefox ESR 91.4.0 (CVE-2021-43542)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:P/I:N/A:N) | Dec 7, 2021 | Dec 8, 2021 | Feb 10, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:N)
Published
Dec 7, 2021
Added
Dec 8, 2021
Modified
Feb 10, 2026
Description
Using XMLHttpRequest, an attacker could have identified installed applications by probing error messages for loading external protocols. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.
Solution
mozilla-firefox-esr-upgrade-91_4
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