Unauthorised Access

Section 1 of the Computer Misuse Act 1990 — headed 'Unauthorised access to computer material' — creates the basic hacking offence. A person is guilty of an offence if he causes a computer to perform any function with intent to secure access to any program or data held in any computer, the access is unauthorised, and he knows at the time when he causes the computer to perform the function that that is the case. The offence does not require the intent to be aimed at any particular target: the intent a person has to have to commit an offence under this section need not be directed at any particular program, data, or computer.

Because the offence turns on intent and knowledge of unauthorised access rather than on any resulting harm, it captures conduct ranging from opportunistic password-guessing to sophisticated intrusion, whether or not anything is copied, damaged, or exfiltrated. A person guilty of the offence is liable, on conviction on indictment, to imprisonment for a term not exceeding two years or to a fine or to both; more serious unauthorised acts that impair a computer's operation, such as deploying malware, are instead charged under section 3 of the Act.