The websites were defaced as the result of change in DNS record of the sites. in a report published by thehackernews hacker confirmed that he managed to hack into Domain registrar of Tajikistan (domain.tr) using Traversal Vulnerability present in the website.

Iranian hacker hacks into Tajikistan Domain registrar  defaces Google  Yahoo  Amazon  twitter    TechWorm - 8Iranian hacker hacks into Tajikistan Domain registrar  defaces Google  Yahoo  Amazon  twitter    TechWorm - 20Iranian hacker hacks into Tajikistan Domain registrar  defaces Google  Yahoo  Amazon  twitter    TechWorm - 31