description: Firefox behaved slightly differently for already known resources when loading CSS resources involving CSS variables. This could have been used to probe the browser history. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.
problem types: Leaking browser history with CSS variables
affected:
{
vendor: Mozilla
product: Thunderbird
versions:
version: unspecified, lessThan: 91.9, status: affected, versionType: custom
}
{
vendor: Mozilla
product: Firefox ESR
versions:
version: unspecified, lessThan: 91.9, status: affected, versionType: custom
}
{
vendor: Mozilla
product: Firefox
versions:
version: unspecified, lessThan: 100, status: affected, versionType: custom
}
