In this blog post, we’ll break down the Top 10 DNS Attack Types you need to know, how they work, and how to protect against them. Whether you’re a cybersecurity expert or a curious learner, this guide is for you.
1. DNS Cache Poisoning Attack
DNS cache poisoning, or spoofing, tricks a DNS resolver into caching a fake IP address. Users are then redirected to malicious sites.
- Impact: Phishing, malware attacks, data theft
- Mitigation: Use DNSSEC, restrict recursive queries
2. DNS Hijacking
This attack modifies DNS settings through malware or credential theft to redirect traffic to harmful sites.
- Impact: Data theft, fake login pages
- Mitigation: Use strong credentials and monitor DNS settings
3. TCP SYN Floods
An attacker sends rapid SYN requests, exhausting server resources and preventing real connections.
- Impact: Denial of service
- Mitigation: SYN cookies, firewall rate limiting
4. Random Subdomain Attack
Floods DNS servers with queries for random, nonexistent subdomains under a legitimate domain.
- Impact: High resource consumption
- Mitigation: Implement rate limiting, caching, anomaly detection
5. Phantom Domain Attack
In this attack, resolvers are directed to domains that don’t respond, tying up system resources.
- Impact: Slowed DNS performance
- Mitigation: Configure timeouts, limit pending queries
6. Domain Hijacking
An attacker takes over a domain name by exploiting registrar vulnerabilities or phishing credentials.
- Impact: Loss of brand control, traffic redirection
- Mitigation: Domain lock, 2FA with registrar
7. Botnet-Based DNS Attacks
Large botnets are used to send DNS traffic to servers, overwhelming them with requests.
- Impact: DDoS attacks, service outages
- Mitigation: Geo-blocking, DDoS mitigation services
8. DNS Tunneling
Data is secretly sent using DNS queries, often to exfiltrate data or establish command-and-control channels.
- Impact: Data leaks, firewall evasion
- Mitigation: DNS traffic monitoring, blocking unused DNS ports
9. DNS Flood Attack
Massive amounts of DNS requests are sent to crash or slow down DNS servers.
- Impact: Denial of service
- Mitigation: Load balancing, scalable DNS services
10. DrDoS (Distributed Reflection Denial of Service)
Uses spoofed requests and open resolvers to reflect large traffic volumes to a victim.
- Impact: Amplified DDoS attacks
- Mitigation: BCP 38 filtering, monitor DNS for abuse
Final Thoughts
DNS attacks are real, evolving threats in today's digital world. By understanding these attack types, you’re already taking the first step in defending your network. Always stay vigilant, and use layered DNS security to protect your infrastructure in 2025 and beyond.