description: If a valid external protocol handler was referenced in an image tag, the resulting broken image size could be distinguished from a broken image size of a non-existent protocol handler. This allowed an attacker to successfully probe whether an external protocol handler was registered. This vulnerability affects Firefox < 82.
problem types: Presence of external protocol handlers could be determined through image tags
affected:
{
product: Firefox
vendor: Mozilla
versions:
lessThan: 82, status: affected, version: unspecified, versionType: custom
}