Data sharing is the controlled exchange of information between participants or systems. In secure environments, it is never just “sending data”; it means deciding who can access which records, under what conditions, and with what logging, validation, and enforcement. The goal is to make information useful without exposing more than necessary.
In cyber security, data sharing matters because it can reduce blind spots for defenders, but it can also widen the attack surface if permissions, formats, or timing are poorly controlled. Attackers often exploit weak sharing controls through excessive access, replay of exposed data, or abuse of trusted integrations. Defenders, by contrast, use governed sharing to support detection, auditing, anti-fraud checks, and interoperable systems. In platform environments such as ad-tech, data sharing can shape competition and security at the same time, so consistency and oversight are essential.