Hacker with nickname AlpHaNiX deface Google, Gmail, Youtube, Yahoo, Yahoo and Apple domains of Democratic Republic of Congo. Hacker use strategy so-called DNS cache poisoning. The compromise occurs when data is introduced into a DNS name server’s cache database that did not originate from authoritative DNS sources. It may be a deliberate attempt of a maliciously crafted attack on a name server. It is a security or data integrity compromise in the Domain Name System (DNS) The compromise is when data. is introduced. into a. DNS name database that didn’t originate. from authoritative sources.
Source: https://thehackernews.com/2011/12/dns-cache-poisoning-attack-on-google.html