CVE-2019-9809
If the source for resources on a page is through an FTP connection, it is possible to trigger a series of modal alert messages for these resources through invalid credentials or locations. These messages cannot be immediately dismissed, allowing for a denial of service (DOS) attack. This vulnerability affects Firefox < 66. Date published : 2019-04-26 https://bugzilla.mozilla.org/show_bug.cgi?id=1282430