CyberGlossary

Attacks & Threats

DNS Spoofing

Also known as: DNS forgery

Definition

An attack that injects falsified DNS responses to redirect victims from a legitimate domain to an attacker-controlled IP address.

DNS spoofing manipulates the Domain Name System resolution process so that a query for a legitimate hostname returns an IP address chosen by the attacker. It can be achieved by tampering with hosts files, intercepting resolver traffic, exploiting weak transaction IDs, or poisoning recursive resolver caches. Once the victim is redirected, attackers harvest credentials, deliver malware, or perform man-in-the-middle interception of TLS sessions with rogue certificates. Defences include DNSSEC validation, encrypted transport (DoH/DoT), randomized source ports and transaction IDs, resolver hardening, and monitoring for anomalous resolution patterns.

Examples

  • Forged responses redirecting banking domain queries to a phishing page.
  • Attackers on an open Wi-Fi network answering DNS queries before the legitimate resolver.

Related terms