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Western Sydney University has suffered yet another cyberattack, highlighting the growing exploitation of DNS (Domain Name System) vulnerabilities. A 2023 IDC study found that 88% of organizations faced DNS-based attacks, averaging seven incidents annually. Cloudflare reported an 80% year-over-year surge in DNS DDoS attacks in Q1 2024, now accounting for 54% of all network-layer attacks. DNSFilter’s 2025 report revealed malicious DNS queries jumped from 1 in 1,000 to 1 in 174 requests.
The National Institute of Standards and Technology (NIST) emphasizes DNS as a critical vulnerability, though stops short of declaring it the single largest threat vector. Given DNS underpins all internet connectivity, robust security measures are non-negotiable.
Full Report: https://lnkd.in/eZxRe-_q
You Should Know: DNS Security Hardening
1. DNSSEC (DNS Security Extensions)
Prevents DNS spoofing by digitally signing DNS records.
Linux Command:
sudo apt install bind9 bind9utils bind9-doc dnssec-tools sudo named-checkconf -z /etc/bind/named.conf
Windows (PowerShell):
Set-DnsServerDnsSecZoneSigning -ZoneName "yourdomain.com" -SignWithNSEC3 $true
2. Rate Limiting DNS Queries
Mitigate DDoS attacks by limiting query rates.
Bind9 Configuration (`/etc/bind/named.conf.options`):
options {
rate-limit {
responses-per-second 10;
};
};
- Block Malicious DNS Queries with Response Policy Zones (RPZ)
Linux (Bind9 RPZ Setup):
zone "rpz" {
type master;
file "/etc/bind/db.rpz";
allow-query { localhost; };
};
Windows (DNS Server Policy):
Add-DnsServerQueryResolutionPolicy -Name "BlockMaliciousDomains" -Action IGNORE -FQDN "eq,malicious.com"
4. Monitor DNS Traffic
Linux (tshark for DNS Monitoring):
sudo tshark -i eth0 -Y "dns" -T fields -e dns.qry.name
Windows (Log Filtering in Event Viewer):
Get-WinEvent -LogName "DNS Server" | Where-Object { $_.Id -eq 1644 }
5. Use DNS Filtering Services
- Cloudflare Gateway (
1.1.1.1) - Quad9 (
9.9.9.9)
Linux (Change DNS Resolver):
sudo nano /etc/resolv.conf nameserver 9.9.9.9
Windows (via Command Line):
netsh interface ip set dns "Ethernet" static 9.9.9.9
What Undercode Say
DNS is the backbone of internet connectivity, yet remains a prime attack surface. Organizations must:
– Enforce DNSSEC to prevent cache poisoning.
– Deploy RPZ to block malicious domains.
– Monitor DNS traffic for anomalies.
– Adopt zero-trust DNS filtering (e.g., Cloudflare, Quad9).
Linux admins should automate DNS logs with journalctl -u named, while Windows admins must audit DNS logs via Get-DnsServerDiagnostics.
Expected Output: A hardened DNS infrastructure resilient against DDoS, spoofing, and exfiltration attacks.
Related Resources:
References:
Reported By: Andy Jenkinson – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
