Matching Attacks to Prevention

Different attacks get past different defences, so different prevention methods limit each one. Match the method to the threat and combine several, because no single method stops every attack.

Attack	Prevention methods	How it limits the attack
Malware	anti-malware software, a firewall, user access levels that stop ordinary users installing software	anti-malware finds and removes it, the firewall blocks traffic that breaks its rules, and users cannot install software themselves
Social engineering and phishing	user access levels, strong passwords, anti-malware software	a fooled account reaches little, a strong password is hard to guess, and anti-malware stops a rogue download
Brute-force	strong passwords, account lockout	a long password makes guessing too slow, and lockout stops attempts after a set number of failures
Denial of service	a firewall	it can block traffic from the addresses sending the attack, which helps keep the service available
Data interception and theft	encryption, physical security	intercepted data is unreadable without the key, and locks and key cards stop devices being taken
SQL injection	penetration testing, user access levels on the database, input validation	authorised testing finds the weakness first, limited database rights shrink the damage, and validation rejects the input

Choosing methods for a scenario

Pick methods that answer the specific threat, and say what each one does. A leisure centre's online class-booking site stores bookings in a database that staff reach through a login page:

Encryption makes the card details unreadable to anyone who intercepts them.
Input validation on the booking form rejects unexpected characters, and staff database accounts have user access levels, so a login cannot read every table. Both limit SQL injection.
Strong passwords with lockout after five failures limit a brute-force attack, and the firewall blocks addresses flooding the site.
Backup drives are kept in a locked cabinet, so a thief cannot take the data.

Choosing methods for a scenario

Practise this