How do i identify & respond to dns infrastructure attacks?
DNS infrastructure attacks can be grouped into four primary types:
- Denial-of-Service (DoS) and Distributed Denial-of-Service (DDoS) attacks: Recognize abrupt increases in DNS query volume, irregular packet dimensions, or corrupted query structures.
- DNS Tunneling: Monitor for suspicious DNS traffic patterns, such as excessive recursive queries, unusual query types (e.g., ANY or AXFR), or queries with unusual TTLs.
- DNS Cache Poisoning: Detect modifications to DNS cache entries, such as unexpected changes to IP addresses or domain names.
- Domain Name Server (DNS) Hijacking: Verify unauthorized changes to DNS records, such as modifications to name servers, glue records, or zone files.
Responding to DNS Infrastructure Attacks
- Implement DNS Security Extensions (DNSSEC): Enable DNSSEC to validate DNS responses and prevent tampering.
- Monitor DNS Traffic: Use tools like DNS logs, network monitoring software, or security information and event management (SIEM) systems to detect anomalies and track attack patterns.
- Filter Malicious Traffic: Implement rate limiting, IP blocking, or content filtering to mitigate DoS/DDoS attacks.
- Update DNS Software and Firmware: Ensure all DNS software and firmware are up-to-date with the latest security patches.
- Restore DNS Configuration: In the event of DNS hijacking, immediately restore the original DNS configuration and notify your registrar and DNS provider.
- Investigate and Contain: Analyze attack patterns, contain the attack, and notify relevant stakeholders, including your registrar, DNS provider, and law enforcement (if necessary).
- Improve DNS Security: Regularly review and improve your DNS security posture by implementing additional measures, such as:
- Enabling DNS query logging and auditing
- Configuring DNS servers to reject malformed queries
- Implementing DNS-based intrusion detection systems (IDS)
By following these guidelines, you’ll be better equipped to identify and respond to DNS infrastructure attacks, ensuring the integrity and availability of your domain name system.