The IT Law Wiki




  • means an unwelcomed entry into an area by force or without permission.
  • "consists of invasive acts that disturb or interrupt one's life or activities."[1]

Information system[]

An intrusion is "unauthorized access to, and/or activity in, an information system."[2]

Intrusion is

[a]n unauthorized act of bypassing the security mechanisms of a network or information system.[3]

Network security[]

An intrusion (also referred to as a network intrusion) is an "unauthorized act of bypassing the security mechanisms of a system."[4]


Intrusion is

[a] communications jamming technique to confuse operators and data processing equipment. It involves the transmission of false messages on victim communication channels.[5]

Overview (Network security)[]

An intrusion may involve unauthorized access or access in excess of a user's privileges on a network. An intrusion is usually accomplished by taking advantage of a system that is not properly configured, a known vulnerability that was not patched, or weak security imple­mentation such as a blank or easily guessed password.

Although insiders have authorized access, they may engage in unauthorized activities, which are considered intrusions. . . . For example, network management technicians have authorized access to routing tables, and they are authorized to engage in defined activities, such as rerouting traffic around congested nodes. However, they are not authorized to alter routing tables to cause congestion nor are they authorized to delete routing tables, and such acts would be considered intrusions.[6]

Once access to the network has been gained, the intruder(s) can exploit the system in various ways. Some examples include —


See also[]