vulnerability

Ubuntu: (Multiple Advisories) (CVE-2021-23984): Firefox vulnerabilities

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Mar 25, 2021
Added
Mar 26, 2021
Modified
Aug 18, 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.

Solutions

ubuntu-upgrade-firefoxubuntu-upgrade-thunderbird
Title
NEW

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