The vulnerability of Mozilla Firefox and Firefox Focus lies in the lack of a warning when switching to a new handler, allowing attackers to exploit it to compromise data integrity.

The vulnerability of Mozilla Firefox and Firefox Focus is related to the lack of a warning when switching to a new protocol handler. Exploiting this vulnerability allows a remote attacker to compromise data integrity...

Mozilla: Lack of warning when opening Diagcab files

The Mozilla Foundation Security Advisory describes this flaw as: When opening Diagcab files, Firefox did not warn the user that these files may contain malicious code...