Passive DNS
Passive DNS is a system that records and stores historical DNS data, such as the mapping between domain names and IP addresses over time. Unlike traditional DNS, which only provides real-time lookups, passive DNS acts like a historical record, allowing you to see how DNS records have changed over time. This is incredibly valuable in cybersecurity investigations.
How Passive DNS Works
Passive DNS systems collect DNS data from various sources, including:
DNS resolvers: Monitoring DNS queries made by users.
DNS zone transfers: Collecting data during zone transfers between DNS servers.
Crawler data: Gathering DNS information from web crawlers that traverse the internet.
This data is then stored in a database and indexed for efficient searching and analysis.
Why Passive DNS is Valuable in Cybersecurity
Tracking malicious activity: Passive DNS can help track the history of malicious domains and IP addresses, revealing patterns and connections that might otherwise be hidden.
Identifying compromised systems: By looking at past DNS records, security teams can identify systems that may have been compromised at some point.
Investigating phishing attacks: Passive DNS can help determine the origin and history of phishing domains, providing valuable investigation clues.
Uncovering botnet infrastructure: Passive DNS can reveal the infrastructure behind botnets by tracking the domain names and IP addresses used to control them.
Detecting malware distribution: Passive DNS can help identify domains and IP addresses involved in malware distribution by tracking their historical associations.
How ThreatNG Leverages Passive DNS
ThreatNG leverages passive DNS data sources to enhance its capabilities:
DNS Intelligence: ThreatNG can correlate its own DNS data with passive DNS information to better understand a domain's history and identify suspicious changes or patterns.
Subdomain Intelligence: ThreatNG can use passive DNS data to discover subdomains that might not be actively used but still pose a security risk.
IP Intelligence: ThreatNG can analyze the historical IP addresses associated with a domain to identify potential malicious activity or connections to known bad actors.
ThreatNG can continuously monitor passive DNS data for any changes related to an organization's domain or IP addresses, alerting security teams to potential threats or compromises.
ThreatNG can enrich its intelligence repositories with passive DNS data, providing more context for investigations and helping to identify emerging threats.
Complementary Solutions and Services
Threat Intelligence Platforms: ThreatNG can integrate with threat intelligence platforms that provide passive DNS data to enhance its threat detection and analysis capabilities.
SIEM Systems: ThreatNG can feed passive DNS data into SIEM systems to provide a more comprehensive view of security events and facilitate incident response.
Examples
Identifying Phishing Domains: ThreatNG uses passive DNS data to determine a newly registered domain that has previously been associated with phishing attacks. This allows the security team to block the domain and protect users proactively.
Uncovering Malware Distribution: ThreatNG detects a sudden increase in DNS queries for a particular domain. By analyzing passive DNS data, it discovers that this domain has historically been associated with malware distribution, allowing the security team to take action to prevent infections.
Key Takeaways
Passive DNS is a valuable tool for cybersecurity investigations. It provides historical context and insights unavailable through traditional DNS lookups.
ThreatNG can leverage passive DNS data to enhance its domain intelligence, continuous monitoring, and threat analysis capabilities.
By integrating with other security tools and services, ThreatNG can provide a comprehensive solution for protecting against a wide range of cyber threats.
