The websites of freebie antivirus vendors AVG and Avira as well as mobile messaging service WhatsApp appear to have been hit by a DNS redirection attack today which sent users to pro-Palestinian websites.

A team of hacktivists calling themselves KDMS have claimed credit for the hacks.

Visitors to avg.com were greeted by a rendition of the Palestinian national anthem (via an embedded YouTube video) and a message from a pro-Palestinian group calling itself the KDMS Team, instead of the usual security tips and links to anti-malware downloads.

"It’s clearly embarrassing for a security company to be hit in this fashion by hackers, but there is no indication that any customer information or sensitive data has been compromised," writes Graham Cluley, a veteran of the antivirus industry turned independent security consultant. "It’s possible that the hackers managed to change the website’s DNS records, redirecting anyone who attempted to visit www.avg.com to a different IP address."

A blog post by Cluley - featuring a screen-shot of the AVG defacement - can be found here.

Security experts were quick to discover that all three victims use hosting biz Network Solutions as their DNS provider. Hackers may have exploited security shortcomings at Network Solutions to alter DNS records and so gain control of their targets' domains.

The KDMS team claims an affiliation with Anonymous Palestine. The same group pulled off a similar DNS hijack / redirection attack against the website of hosting firm leaseweb.com over the weekend.

LeaseWeb's statement on the attack can be found here.

Leaseweb denied earlier reports that a vulnerability in its WHMCS billing and support system software might have been responsible for the hijack, but without naming a cause. The hosting firm is seeking to play down the significance of the attack, which it characterises as regrettable but superficial and quickly resolved.

Update

A spokeswoman for AVG said: "AVG can confirm today that it has had a select number of online properties defaced as a result of our DNS provider being compromised. A number of other companies appear to have been similarly targeted. The situation is being monitored and assessed. Customers are our priority and AVG is working hard to resume normal service levels to its customer base."

An Avira spokesperson said: "Today we have experienced a major disruption in our DNS service. It appears that several websites of Avira as well as other companies have been compromised by a group called KDMS. The websites of Avira have not been hacked, the attack happened at our internet service provider, Network Solutions."

El Reg has also contacted Network Solutions for comment, but they had not responded at the time of publication. We'll update if we hear more. ®

Bootnote

Thanks to Reg reader Kevin G, who was the first to advise us that AVG website visitors were getting their surfing sessions hijacked, as well as correctly diagnosing the DNS chicanery behind the attack.