A method and system for assessing the data leakage threat associated with third-party tags on a particular website, such as a content publisher site, is assessed by mimicking a standard web browser. Each third-party tag on the site is identified and investigated in a hierarchical manner, and a data leakage threat score is assigned to each third-party tag based on certain attributes associated with the tag and the resource linked by the third-party tag. A cumulative data leakage threat score is then calculated to determine if the site is a data leakage threat, such as a threat for misuse of a consumer's data.