A network share is a folder or drive published on a server so other computers can access files over the network. In Windows environments, shares are often used for collaboration, software distribution, backups, and shared business data. Access is controlled with permissions, authentication, and sometimes network segmentation.
In cyber security, network shares matter because they are common targets during lateral movement. Once attackers get valid credentials or a foothold on one machine, they may browse shares to find sensitive files, map the internal network, copy data, or drop malware on other systems. Ransomware crews also abuse shares to spread encryption and disrupt recovery. Defenders reduce risk by limiting share access, enforcing least privilege, monitoring unusual file activity, and reviewing logs for remote enumeration, mass reads, or abnormal writes.