Origin Validation Error
Through use of reportValidity() and window.open(), a plain-text validation message could have been overlaid on another origin, leading to possible user confusion and spoofing attacks. This vulnerability affects Firefox < 93, Thunderbird < 91.2, and Firefox ESR < 91.2.
CWE-346 - Origin Validation Error
The software does not properly verify that the source of data or communication is valid.