Sandboxie is Windows isolation software that runs applications in a controlled environment, limiting their access to parts of the system. This can help contain untrusted programs and reduce the consequences of unsafe behavior, though it is not a substitute for other security controls.
In cyber security, Sandboxie can also appear as a legitimate executable in an attack chain. An attacker may use DLL sideloading to make a trusted program load a malicious library; the use of Sandboxie does not by itself mean the software is vulnerable or that its isolation has been defeated. Defenders should examine which DLLs are loaded and from where, as well as the process’s behavior, rather than relying on an executable’s familiar name or reputation.