DNS Security
The practice of protecting Domain Name System infrastructure from attacks and abuse, including DNS hijacking, spoofing, and cache poisoning, to ensure reliable and secure domain name resolution.
In-Depth Explanation
DNS security encompasses the tools and protocols used to protect the Domain Name System - the internet's phone book that translates domain names into IP addresses. Because nearly all internet activity begins with a DNS query, DNS is a critical attack surface.
DNS threats:
- DNS spoofing/cache poisoning: Inserting false DNS records to redirect traffic
- DNS hijacking: Taking control of DNS settings to redirect domains
- DNS tunnelling: Using DNS queries to exfiltrate data or bypass firewalls
- DDoS on DNS: Overwhelming DNS servers to disrupt service
- Domain shadowing: Creating subdomains under compromised domains for malicious use
- Typosquatting: Registering similar domain names to capture mistyped URLs
DNS security measures:
- DNSSEC: Cryptographic authentication of DNS responses
- DNS filtering: Blocking access to known malicious domains
- DoH/DoT: Encrypting DNS queries (DNS over HTTPS/TLS)
- DNS monitoring: Logging and analysing DNS queries for anomalies
- Registrar security: Locking domain registrar accounts with MFA
- Split DNS: Separating internal and external DNS resolution
DNS filtering for security:
- Block access to known malware, phishing, and command-and-control domains
- Prevent users from accessing inappropriate or dangerous websites
- Enforce acceptable use policies at the network level
- Popular services: Cisco Umbrella, Cloudflare Gateway, DNSFilter
Business Context
DNS is involved in over 90% of malware attacks, making DNS security one of the most effective and overlooked security layers. DNS filtering alone can block a significant proportion of threats before they reach endpoints.
How Clever Ops Uses This
Clever Ops implements DNS security for Australian businesses including DNS filtering to block malicious domains, DNSSEC to prevent spoofing, registrar account protection, and DNS monitoring for threat detection. We deploy cloud-based DNS security that protects all devices regardless of location.
Example Use Case
"An Australian business implements Cloudflare Gateway for DNS filtering, blocking access to malicious domains across all offices and remote workers. Within the first month, DNS filtering blocks over 3,000 attempts to access phishing and malware sites."