False negative and True negative

In the context of security, a false negative and a true negative refer to the results of a security system’s detection capabilities.

A false negative, also known as a “miss,” is when a security system fails to identify a security threat, such as a malware or intrusion attempt. False negatives can occur when a security system is not configured properly or when a threat uses a new or unknown method to bypass the security system. False negatives can lead to undetected security breaches and can cause significant damage to an organization.

A true negative, on the other hand, is when a security system correctly identifies that an event or activity is not a security threat. For example, a security system correctly identifying a legitimate login attempt or a harmless email. True negatives indicate that the security system is functioning correctly and that no potential threats have been detected.

It’s important for security systems to have a balance between false negatives and true negatives, as too many false negatives can lead to undetected security breaches, while too many true negatives can lead to an unnecessary amount of security alerts. The ideal situation is to have a low rate of false negatives and a high rate of true negatives, this is called “Recall” in the security field.  

Here are some examples of false negatives and true negatives in the context of security:

False Negative:

A security system fails to detect a malware-infected file because the malware uses a new and unknown method of infection.

A security system fails to detect a phishing email because the email uses a new and unknown tactic to bypass the system’s filters.

A security system fails to detect an intrusion attempt because the attacker uses a new and unknown exploit.

True Negative:

A security system correctly identifies that a login attempt is legitimate and allows the login to proceed.

A security system correctly identifies that an email is not spam and allows the email to be delivered to the inbox.

A security system correctly identifies that a file is not malware-infected and allows the file to be downloaded.

In all these examples, the security system is working correctly, and no threats are detected. A low rate of false negatives and a high rate of true negatives is the ideal situation for security systems, as it means that the system is detecting threats effectively without generating unnecessary alerts.

False positive and True positive

In the context of security, a false positive and a true positive refer to the results of a security system’s detection capabilities.

A false positive, also known as a “false alarm,” is when a security system incorrectly identifies a benign event or activity as a security threat. For example, a security system may flag a legitimate email as spam or flag a legitimate login attempt as a hacking attempt. False positives can cause unnecessary alarm and can also lead to legitimate traffic being blocked or quarantined.

A true positive, on the other hand, is when a security system correctly identifies a security threat. For example, a security system correctly identifying a phishing email or a malware-infected file. True positives indicate that the security system is functioning correctly and that a potential threat has been detected.

It’s important for security systems to have a balance between false positives and true positives, as too many false positives can lead to a lack of trust in the security system, while too many true positives can overwhelm security teams. The ideal situation is to have a low rate of false positives and a high rate of true positives, this is called “Precision” in the security field.

Here are some examples of false positives and true positives in the context of security:

False Positive:

A security system flags a legitimate email as spam.

A security system flags a legitimate login attempt as a hacking attempt.

A security system flags a harmless file as malware infected.

True Positive:

A security system correctly identifies a phishing email and quarantines it.

A security system correctly identifies a malware-infected file and quarantines it.

A security system correctly identifies an intrusion attempt and blocks it.

In all these examples, the security system is working correctly, and threats have been detected. A low rate of false positives and a high rate of true positives is the ideal situation for security systems, as it means that the system is detecting threats effectively without generating unnecessary alerts.

By Michael

Writer of Infohaunt is an Cyber Security Professional have experience in SOC operations, Threat Management, Incident Response, Threat Hunting, Digital Forensics.