Which activity is specifically related to unauthorized data transfer to third parties?

Data exfiltration refers specifically to the unauthorized transfer of data from an organization's systems to an external party. This activity typically involves stealthily extracting sensitive information, often by circumventing security measures. In a counterintelligence context, monitoring for signs of data exfiltration is crucial, as it indicates a potential security breach where critical data may be at risk of being disclosed or misused by adversaries.

In contrast, a data breach generally encompasses any incident where unauthorized individuals gain access to sensitive data, which may include exfiltration but is broader in scope. Data backups involve creating copies of data for recovery purposes and do not inherently relate to unauthorized transfers. Data encryption is a security measure used to protect data by converting it into a coded format, also not directly associated with the act of transferring data to unauthorized third parties. Thus, the focus on unauthorized data transfer makes data exfiltration the most relevant option in this context.