Some registrars use wildcard DNS systems to redirect users to their own sites when a DNS lookup fails in such cases as a non-existent domains. ICANN's Security and Stability Advisory Committee (SSAC) wants to ban the practice.
According to a report issued by the SSAC, wildcard DNS at the TLD level (and lower levels) is a "destabilizing practice," which among other issues can lead to DNS abuse. SSAC suggested that ICANN prohibit the practice at TLD registries.
When put into practice, wildcard redirection typically occurs when domain names are mistyped, or have expired, or are registered but not put into use, or are not registered at all. TLD operators use the practice to drive traffic to destinations of their choosing. However, SSAC said that such practice is risky, can lead to various attacks, and can put Internet users into precarious circumstances.
