DNS Security: Why It Matters More Than You Think

Between 80 and 90 percent of cyber attacks move through the Domain Name System, and most Canadian organizations barely watch it. DNS quietly resolves every web request your staff make. When it goes unmonitored, attackers use it as an open door into your network. This post explains why DNS security deserves your attention and what you do about it.

DNS works like the address book of the internet. It translates a name such as cyber.gc.ca into the numeric IP address a machine needs. Every email link, cloud login, and software update starts with a DNS lookup. The protocol is old, trusting, and rarely inspected. Attackers know this. They hide inside normal-looking DNS traffic because few defenders inspect it.

Why attackers love DNS

DNS traffic flows freely through most firewalls. Security teams block risky ports and filter web browsing, but they leave DNS wide open. An attacker uses this gap in several ways. They register a malicious domain, trick a staff member into clicking a link, and the resulting lookup connects the victim to a server under their control. Malware already inside your network uses DNS to reach its command server. Some groups smuggle stolen data out through DNS queries, a method called DNS tunnelling.

The Canadian Centre for Cyber Security documents these risks in its guidance on DNS tampering (ITSAP.40.021). Threat actors redirect your traffic, poison DNS caches, and hijack domains to intercept sensitive information. A single successful redirect sends your users to a fake login page and harvests their credentials. You never notice the switch because the web address in the browser looks correct.

The Canadian response: protective DNS

Protective DNS closes the blind spot. Instead of resolving every request without question, a protective resolver checks each domain against threat intelligence before it answers. When a lookup points to a known malicious site, the resolver blocks it. Your user never reaches the dangerous page. The Cyber Centre recommends this approach in its guidance on Protective Domain Name System (ITSAP.40.019), and it maps directly to the CCCS Baseline Cyber Security Controls for small and medium organizations.

Canada runs one of the strongest examples of this model. CIRA, the authority behind the .ca domain, operates a protective DNS service built on Cyber Centre threat intelligence. CIRA adds more than 100,000 new malicious domains to its blocklists every day and protects millions of Canadian users. For organizations, its DNS Firewall extends the same filtering across staff devices and networks. Those numbers matter because the Cyber Centre identifies roughly 400 new malicious websites each day. Threats move fast. A blocklist refreshed once a week protects nothing. Protective DNS works because it updates constantly and acts at the moment of the lookup, before a connection forms.

What DNS security looks like in practice

Start by pointing your organization to a protective resolver. Replace default ISP DNS settings with a trusted service or a paid enterprise resolver. Configure it across every device, including remote laptops and mobile phones. An unmanaged home network undoes your office controls, so extend the policy to staff working from home.

Logging is the second half. Turn on DNS query logging and review it. Repeated lookups to a strange domain signal malware beaconing out. A sudden spike in failed resolutions points to misconfiguration or an active attack. Your analysts read these logs the same way they read firewall and endpoint data. DNS becomes a source of early warning instead of a blind spot.

Segmentation reinforces the effort. Internal DNS servers should answer only internal queries. External resolvers handle the rest. When you separate the two, a compromised workstation struggles to reach attacker infrastructure. Pair this with firewall rules from the Cyber Centre guidance, and you close the gaps attackers rely on.

Where training fits

Tools alone do not secure DNS. Your people need to understand the protocol and read its signals. A network practitioner configures resolvers and segmentation correctly. A security analyst spots the beaconing pattern buried in query logs. An incident handler traces a redirect back to its source and contains it.

Mile2 builds these skills through role-based training. The Certified Network Practitioner program grounds you in the network fundamentals DNS depends on. The Certified Cybersecurity Analyst track teaches you to monitor traffic and detect anomalies across sources like DNS. For teams handling active intrusions, the Certified Incident Handling Engineer covers containment and response. Leaders who set policy benefit from the Certified Information Systems Security Officer program, which ties controls like protective DNS to a wider risk framework.

The bottom line

DNS runs under everything your organization does online. Attackers treat it as an entry point, a control channel, and an exit route. You defend it with protective resolution, constant logging, and trained people who know what healthy DNS traffic looks like. Canada gives you the guidance and the free tools to start today. Point your resolvers at a trusted service, watch your query logs, and turn your quietest protocol into one of your best sources of warning.