It was possible to move the cursor using pointerlock from an iframe. This allowed moving the cursor outside of the viewport and the Firefox window. This vulnerability affects Firefox < 128 and Thunderbird < 128.
[
{
"product": "Firefox",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "128",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
},
{
"product": "Thunderbird",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "128",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
}
]