Organisations are often attacked by customised malware. In such cases, supervisors (for example) are tricked into opening harmful e-mail attachments through social engineering. Customised malware often cannot be detected immediately by virus protection programs. The human resources department of an organisation can also be the target—for example, if it is sent electronic job application documents that are infected with malware. If an attacker manages to infect an IT system using such methods, they may infiltrate other areas of the corresponding organisation and view, manipulate, or destroy information.