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Subfinder

Open Source

About Subfinder

Subfinder is an open-source tool designed for passive subdomain enumeration, enabling cybersecurity teams to discover valid subdomains efficiently using curated online sources. It is optimized for speed and stealth, making it ideal for penetration testers, bug bounty hunters, and vulnerability management teams seeking comprehensive visibility into an organization's external attack surface. The tool's modular architecture and lightweight resource usage allow seamless integration into existing security workflows.

Subfinder supports multiple output formats and offers flexible configuration options to tailor subdomain discovery processes, including source selection, recursive enumeration, and filtering capabilities. By leveraging passive data sources, it ensures compliance with source licenses while maintaining operational stealth, reducing the risk of detection during reconnaissance activities. This makes Subfinder a valuable asset for enterprises aiming to enhance their vulnerability management and external threat detection strategies.

Key Capabilities

  • ✓Passive subdomain enumeration using curated online sources
  • ✓Fast resolution and wildcard elimination modules
  • ✓Multiple output formats including JSON and file
  • ✓Configurable source selection and recursive scanning
  • ✓Lightweight with STDIN/OUT support for workflow integration

Integrations

GitHub ActionsCI/CD pipelinesSecurity orchestration tools

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Quick Facts

github.com/projectdiscovery/subfinder
CategoryCybersecurity
SubcategoryVulnerability Management
PricingOpen Source
DeploymentOpen Source
Target SizeEnterprise