A supervisory authority is a public regulator that oversees data-protection compliance. Under laws such as the GDPR, it can receive complaints, investigate organizations, demand documents, inspect security controls, and order corrective measures such as stopping processing, fixing policy gaps, or notifying affected users.
In cybersecurity, supervisory authorities matter because privacy incidents are often also security incidents. After a breach, they may examine access logs, retention practices, encryption, breach-response timing, and whether the organization had appropriate technical and organizational measures in place. Attackers do not target the authority itself, but the authority can shape the defense by forcing stronger controls, better incident reporting, and clearer accountability. For defenders, keeping evidence of risk assessments, monitoring, and containment steps helps demonstrate compliance when an intrusion or data leak is reviewed.