vulnerability
MFSA2021-10 Firefox: Security Vulnerabilities fixed in Firefox 87 (CVE-2021-23984)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Mar 23, 2021 | Mar 24, 2021 | Aug 11, 2025 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Mar 23, 2021
Added
Mar 24, 2021
Modified
Aug 11, 2025
Description
A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.
Solution
mozilla-firefox-upgrade-87_0
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