DNS security for smart grids is the practice of monitoring, filtering, and defending the Domain Name System that modern utilities rely on for device authentication, cloud connectivity, and customer-facing services. It matters because DNS is one of the most trusted and least monitored layers of utility infrastructure, and attackers are increasingly starting there rather than inside substations or control systems.
Why is DNS security critical for smart grids and utilities right now?
DNS security is critical because state-linked attackers are already positioning inside grid-adjacent networks, and DNS underpins nearly everything a digital utility does. During a December 2, 2025 U.S. House Energy and Commerce subcommittee hearing, security experts warned that Chinese state-sponsored groups, including Volt Typhoon and Salt Typhoon, have been pre-positioning inside networks that support the U.S. electric grid, seeking long-term access well before any disruption occurs.
That warning lands as utilities rapidly expand smart grids, renewable generation, cloud platforms, and battery energy storage systems (BESS). In its 2026 Year in Review, OT security firm Dragos reported tracking 26 threat groups worldwide capable of targeting industrial and critical infrastructure, 11 of them active in 2025, with several, such as Voltzite, focused specifically on long-term persistence inside the electric sector. As the grid becomes more connected, the attack surface grows with it.
Why are smart grids becoming harder to defend
Smart grids are harder to defend because they are no longer the isolated, air-gapped systems they once were. Smart meters, IoT sensors, and cloud-connected SCADA platforms now sit alongside legacy control systems, and every new connected device widens what an attacker can reach. The number of connected IoT devices surpassed 21 billion in 2025 and is projected to approach 39 billion by 2030, and each substation, sensor, and grid-balancing device added to the network is one more endpoint to secure.
This digitisation is necessary. Smart grids depend on real-time data to balance renewable generation, manage demand, and prevent cascading outages. But it also leaves utilities managing a far larger and more distributed attack surface than before. As cloud services, connected substations, APIs, and IIoT devices multiply, the visibility, segmentation, and continuous monitoring expected by frameworks such as NERC CIP and IEC 62443 become progressively harder to maintain. Cybersecurity maturity is also uneven across the sector: many smaller municipal utilities and rural cooperatives face workforce and budget constraints that make advanced monitoring difficult to implement at the pace of larger operators.
Why is DNS the most overlooked attack surface in utilities?
DNS is the most overlooked attack surface because it sits underneath almost everything device authentication, service discovery, cloud connectivity yet most security teams have little visibility into it. A 2025 Forrester Consulting study commissioned by EfficientIP, surveying 218 senior security decision-makers across North America and Europe, found that 95% of organisations experienced a DNS-related cyberattack or vulnerability in the previous year, while 67% reported lacking sufficient visibility into DNS traffic, analytics, and threat intelligence.
That gap matters because DNS-layer attacks rarely resemble traditional intrusions. Recent disclosures reinforce how fragile core DNS infrastructure can be: in January 2026, CVE-2025-13878 a high-severity (CVSS 7.5) denial-of-service flaw in ISC BIND disclosed by Marlink Cyber showed that even one of the world’s most widely deployed DNS servers can be crashed remotely by a single malformed request. There is no evidence the flaw was exploited in the wild, and a patch was released, but it highlights how weaknesses in core DNS can disrupt name resolution across critical environments if left unpatched.
What DNS-specific threats target smart grids and utilities:
DNS amplification DDoS
Attackers abuse misconfigured open DNS resolvers to turn small requests into massive traffic floods that overwhelm internet-facing services. It re-emerged as one of the leading reflection/amplification vectors in 2025, with threat-intelligence reporting a sharp year-over-year rise in open-resolver abuse.
DNS tunneling
Attackers hide command-and-control traffic inside DNS queries and responses. MITRE ATT&CK documents dozens of malware families and APT groups using DNS-based communication precisely because the protocol is trusted, ubiquitous, and often inspected less than web traffic.
DNS delegation hijacking ("Sitting Ducks")
Attackers exploit misconfigurations such as lame delegations to hijack legitimate domains without ever compromising the registrar account. Joint research by Infoblox and Eclypsium estimated more than one million domains were vulnerable, with tens of thousands already hijacked.
Most legacy tools standard firewalls, intrusion prevention systems, endpoint detection were never built to inspect DNS in depth. They miss the signals that matter most at this layer: unusual query patterns, algorithmically generated domains, and abnormal spikes in failed lookups. That blind spot is exactly where an attacker can operate undetected for months.
Proven in the Utilities Sector
One leading power utility deployed Prophaze WAAP to protect grid operations, billing, payment platforms, and customer-facing APIs from SQL injection, bot-driven abuse, Layer 7 DDoS attacks, and zero-day threats,maintaining zero service downtime while improving visibility across its digital infrastructure.
Why do traditional defenses fall short for utility DNS?
Traditional defences fall short because security tools built for enterprise IT rarely translate cleanly to environments where uptime is non-negotiable and legacy OT systems cannot simply be patched or replaced. Because DNS operates beneath the applications utilities actually monitor underpinning authentication, service discovery, and connectivity attacks at the DNS layer can stay invisible until they disrupt critical services or enable a deeper compromise.
What is DNS security, and what does modern DNS security solve?
What is DNS security? DNS security is the practice of protecting an organisation’s DNS infrastructure through continuous monitoring, filtering, and threat detection at the DNS layer, rather than relying only on application or network-layer defence.
For smart grids and digital utilities, the shift from legacy handling to modern DNS security should look like this:
In practice, this helps utilities:
- Detect and mitigate DNS amplification and volumetric DDoS attacks before they affect customer-facing or grid-adjacent systems.
- Identify DNS tunneling attempts that indicate a persistent foothold inside the network.
- Reduce exposure from dangling or forgotten DNS records.
- Maintain the kind of continuous monitoring that NERC CIP and IEC 62443 increasingly expect.
How Prophaze Addresses Smart Grid and Utility Security Challenges
Utilities are defending an expanding attack surface across smart meters, cloud-connected SCADA platforms, customer portals, and distributed digital services. Prophaze secures this environment with its DNS Security Platform, combined with WAAP and Layer 7 DDoS protection across cloud, on-premise, multi-cloud, and Kubernetes environments.
With Prophaze utilities can:
- Block malicious DNS requests using continuously updated threat intelligence to stop connections to malware, phishing, and command-and-control domains.
- Protect DNS infrastructure from flood, amplification, and query-based DDoS attacks with automated detection and mitigation.
- Strengthen DNS integrity with DNSSEC while gaining real-time visibility into DNS queries, suspicious activity, and attack trends.
- Detect reconnaissance and DNS-based attacks through subdomain enumeration monitoring, attacker IP identification, and detailed security analytics.
- Maintain resilient DNS operations with dedicated nameservers, tenant isolation, and multi-cloud high availability.
By combining DNS Security, WAAP, and Layer 7 DDoS protection, Prophaze helps utilities improve resilience and visibility across critical digital infrastructure while supporting NERC CIP and IEC 62443 -aligned programmes.
- Strengthen your smart grid and utility security posture
State-linked threat actors are already positioned inside grid-adjacent networks, and DNS remains one of the most exploited yet least monitored layers of utility infrastructure. Prophaze helps digital utilities monitor, protect, and secure their DNS, applications, and APIs in real time, without adding complexity to already demanding OT and IT security programmes.
Frequently Asked Questions (FAQ)
1. Why does DNS security matter for smart grids and utilities?
DNS underpins device authentication, cloud connectivity, and customer-facing services across modern utilities, yet 67% of organisations lack meaningful visibility into their own DNS traffic, making it an attractive, under-monitored target.
2. What is DNS tunneling and why is it a concern for critical infrastructure?
DNS tunneling hides unauthorized data or communication inside DNS queries, allowing attackers to maintain long-term, low-visibility persistence inside a network, a technique associated with advanced state-linked threat groups.
3. How does DNS amplification DDoS affect utilities?
Attackers abuse misconfigured open DNS resolvers to flood a target with traffic using minimal bandwidth of their own. This vector overtook memcached as the leading DDoS amplification method in 2025.
4. How do NERC CIP and IEC 62443 relate to DNS security?
Both frameworks expect continuous monitoring and network segmentation across utility environments, expectations that are difficult to meet without visibility into DNS traffic, which legacy firewalls and endpoint tools typically miss.
5. How does Prophaze support utility cybersecurity?
Prophaze combines DNS Security, WAAP, and Layer 7 DDoS protection to give utilities continuous visibility into DNS, application, and API traffic, supporting operational resilience alongside existing NERC CIP and IEC 62443-aligned programmes.
