Which three of the following scenarios can be defined as information security incidents?

You are carrying out your first third-party ISMS surveillance audit as an Audit Team Leader. You are presently in the auditee’s data centre with another member of your audit team.

Your colleague seems unsure as to the difference between an information security event and an information security incident. You attempt to explain the difference by providing examples.

Which three of the following scenarios can be defined as information security incidents?
A . The organisation’s malware protection software prevents a virus
B . A hard drive is used after its recommended replacement date
C . The organisation receives a phishing email
D . An employee fails to clear their desk at the end of their shift
E . A contractor who has not been paid deletes top management ICT accounts
F . An unhappy employee changes payroll records without permission
G . The organisation fails a third-party penetration test
H . The organisation’s marketing data is copied by hackers and sold to a competitor

Answer: E, F, H

Explanation:

According to ISO/IEC 27000:2018, which provides an overview and vocabulary of information security management systems, an information security event is an identified occurrence of a system, service or network state indicating a possible breach of information security policy or failure of safeguards, or a previously unknown situation that may be security relevant1. An information security incident is a single or a series of unwanted or unexpected information security events that have a significant probability of compromising business operations and threatening information security1. Therefore, based on this definition, three examples of information security incidents are: A contractor who has not been paid deletes top management ICT accounts: This is an example of an unwanted or unexpected information security event that has a significant probability of compromising business operations and threatening information security, as it may result in loss of access, data, or functionality for the top management.

An unhappy employee changes payroll records without permission: This is an example of an unwanted or unexpected information security event that has a significant probability of compromising business operations and threatening information security, as it may result in financial fraud, legal liability, or reputational damage for the organization.

The organisation’s marketing data is copied by hackers and sold to a competitor: This is an example of an unwanted or unexpected information security event that has a significant probability of compromising business operations and threatening information security, as it may result in loss of confidentiality, competitive advantage, or customer trust for the organization.

The other options are not examples of information security incidents, but rather information security events that may or may not lead to incidents depending on their impact and severity. For example: The organisation’s malware protection software prevents a virus: This is an example of an identified occurrence of a system state indicating a possible breach of information security policy or failure of safeguards, but it does not have a significant probability of compromising business operations and threatening information security, as it is prevented by the malware protection software.

A hard drive is used after its recommended replacement date: This is an example of an identified occurrence of a system state indicating a possible breach of information security policy or failure of safeguards, but it does not have a significant probability of compromising business operations and threatening information security, unless it fails or causes other problems.

The organisation receives a phishing email: This is an example of an identified occurrence of a network state indicating a possible breach of information security policy or failure of safeguards, but it does not have a significant probability of compromising business operations and threatening information security, unless it is opened or responded to by the recipient.

An employee fails to clear their desk at the end of their shift: This is an example of an identified occurrence of a service state indicating a possible breach of information security policy or failure of safeguards, but it does not have a significant probability of compromising business operations and threatening information security, unless the desk contains sensitive or confidential information that is accessed by unauthorized persons.

The organisation fails a third-party penetration test: This is an example of an identified occurrence of a system state indicating a possible breach of information security policy or failure of safeguards, but it does not have a significant probability of compromising business operations and threatening information security, unless the penetration test reveals serious vulnerabilities that are exploited by malicious actors.

Reference: ISO/IEC 27000:2018 – Information technology C Security techniques C Information security management systems C Overview and vocabulary