Defacement page titled ‘You got Pwned’ with Anonymous Logo and playing Palestinian national anthem in the page background. It seems that the hacker used DNS hijacking to point domains on a fake server with deface page. The Whatsapp has resolved the issue, but at the time of writing AVG is still defaced. It is not clear that if any user data was compromised from AVG or Whatsapp. Just two days before, KDMS Team hacked LeaseWeb, one of the world’s biggest hosting company.
Source: https://thehackernews.com/2013/10/whatsapp-and-avg-antivirus-firm.html