Detectors

Learn about Nightfall detectors.

A Detector is a tool that scans any online entity to detect if any sensitive data is present in the entity. An "entity" can refer to any resource on the Internet like a file in Google Drive, ticket data in JIRA, code snippets in GitHub, customer data in Salesforce, and so on.

There are two types of detectors; Nightfall Detectors and Custom Detectors.

Nightfall Detectors

Nightfall provides a comprehensive library of machine learning–powered detectors that identify sensitive data across text, images, files, and source code with 90%-95% precision out of the box. All detectors are available immediately in your workspace under Detection → Detectors

Detectors power the core of Nightfall’s data protection capabilities. They allow you to quickly scan and classify content for risks such as PII, PHI, financial data, credentials, intellectual property (IP), confidential corporate documents, and more.

Nightfall offers two primary types of detectors:

1. Entity Detectors

Entity Detectors identify specific pieces of sensitive information—such as an SSN, a driver’s license number, credit card number, password, or an api key —where the format is known and can be validated.

Entity Detectors use:

• Pattern recognition

• Natural-language context

• Validation logic

• ML-based disambiguation

These detectors are ideal when you need precise identification of well-defined data types (e.g., U.S. Social Security Numbers, credit card numbers, or country-specific passport IDs).

Examples of When Entity Detectors Are Useful

• Detecting employees’ personal data in outbound messages

• Preventing customer PII leaks (e.g., driver's license numbers)

• Flagging financial identifiers in logs or repositories

• Monitoring exposed secrets or API keys

Entity Detectors answer the question: “Does this content contain PII, PCI, PHI, or credentials?”

2. File Classifiers

File Classifiers identify intellectual property and confidential documents—your organization’s crown jewels—based on a file’s content, structure, and semantic meaning, not just the presence of individual data types like PII or API keys.

10MB

file classifiers.mp4

Open

Instead of asking “Does this file contain a sensitive string?”, File Classifiers answer a more important question:

“What type of document is this, and how sensitive is it?”

What File Classifiers Detect

File Classifiers are designed to identify entire document types, including:

• Proprietary source code and internal algorithms

• Confidential business documents and internal reports

• Unreleased product materials and R&D artifacts

• Financial statements, forecasts, tax files, and regulatory drafts

• Legal agreements, contracts, and NDAs

• Patient and medical records

• Customer lists and account data

• Images of physical documents (e.g., passports, IDs, credit cards)

How File Classification Works

To classify files accurately, Nightfall analyzes signals across the full document, including:

• Writing style and technical terminology

• Domain-specific language (legal, engineering, HR, finance, healthcare)

• File structure (headings, tables, templates, layouts)

• Semantic meaning at the paragraph and document level

• Visual elements in scanned or image-based documents

Why This Matters

By understanding what a document is, not just what it contains, File Classifiers enable you to detect and protect your most business-critical assets from:

• Accidental sharing

• Insider risk

• Malicious exfiltration

This approach closes the gap where traditional, entity-based DLP falls short.

To view the detectors of a specific category, click the category name. All the Nightfall detectors' category names are highlighted in the above image.

For the complete list of all the detectors present in all the categories, you can view the Nightfall Detector Glossary document.

Now that you are aware of all the available detectors, you can choose to use any of the existing Nightfall detectors or create your detector specific to your organization's requirements. If you are not sure of which Nightfall detector to use, view the Choosing a Nightfall Detector document.

If Nightfal detectors can address your organization's requirements and you do not wish to create any custom detectors, you can refer to the Create Detection Rules document, to learn about how to add detectors to a detection rule.

If Nightfall detectors cannot address your organization's requirements, you can create your own detector(s) or customize a Nightfall detector. You can refer to the Creating Custom Detectors document to learn about custom detectors.