Taking advantage of vulnerabilities in certain protocols
Application
Some hackers utilize computer programs to attack networks. Often, a hacker gains access
to a machine through a web-based application or an email-related program. The most
popular members of this type are:
Sending “spam” (i.e. junk mail) to people
Installing malware (i.e. malicious software) in target systems
Bypassing security mechanisms (e.g. firewall) through “online” protocols (e.g.
SMTP, HTTP, IMAP, etc.)