Malicious code can be delivered in a number of ways. Some of the most common include:
Malicious websites or compromised websites
Phishing emails, with malicious email attachments
Malicious ads with spyware
Malicious software installed on devices
Other infected computers or mobile devices
The ease with which malware can reach your systems means you need to look at layered security, along with teaching cyber security awareness and best practices to your team, in order to prevent unauthorised access to your sensitive data.