CISSE Advanced Level
Information Systems Security glossary
Every term this guide defines, A to Z, each with the chapter that teaches it. Open it when a word in a question is unfamiliar, and test yourself on it in the last week: cover the definition and say it in one sentence.
6 terms from the free first chapter
A
- Availability
Information and systems are accessible to authorised users when needed. Breached by a denial-of-service attack, a ransomware lockout, a failed server with no backup.
Taught in Overview of information systems security
C
- Confidentiality
Information is disclosed only to those authorised to see it. Breached by an unauthorised read, a leaked customer database, a screen left visible to a passer-by.
Taught in Overview of information systems security
I
- Integrity
Information is accurate and has not been altered without authorisation. Breached by an unauthorised write, a tampered exam script, a manipulated bank balance.
Taught in Overview of information systems security
R
- Risk
The likelihood of a threat exploiting a vulnerability, combined with the impact if it does. Risk is what is actually managed; a threat with no exploitable vulnerability, or a vulnerability no threat can reach, carries no real risk.
Taught in Overview of information systems security
T
- Threat
A potential cause of an unwanted incident, a malicious actor, a natural disaster, a hardware failure. A threat exists independently of any particular organisation.
Taught in Overview of information systems security
V
- Vulnerability
A weakness that a threat can exploit, an unpatched system, a weak password policy, a building with no fire suppression. Vulnerabilities are specific to the organisation's own environment.
Taught in Overview of information systems security
The full glossary adds every term from the other 10 chapters, A to Z, each with the chapter that teaches it.