A hacker today redirected web surfers looking for Yahoo, Microsoft or Google to a page showing a TV test card by apparently poisoning Google's public DNS system.
Punters and organisations relying on Google's free service were affected, rather than the websites themselves being compromised.
Visitors to yahoo.ro, microsoft.ro and google.ro were served a message from an Algerian miscreant using the moniker MCA-CRB. Traffic destined for the Romanian websites of Kaspersky Lab and Paypal was also hijacked. Affected web browsers were pointed to a frankly boring message resembling nothing more than a test card and an animated GIF background.
MCA-CRB is a prolific online graffiti artist who has defaced at least 5,000 sites, according to records kept by Zone-H. The latest attack was carried out to gain bragging rights rather than to trouser a profit or stage a political protest.
Costin Raiu, a senior security researcher at Kaspersky Lab, said "the problem is with the Google free DNS servers (22.214.171.124, 126.96.36.199) not with the DNS servers for the specific domains". His colleague Stefan Tanase believes Google's public DNS servers were tricked into giving out the wrong IP addresses for the affected domains; one way this attack can be pulled off is by poisoning the web giant's DNS cache with bogus entries.
Other experts think the problem originates further up the food chain at Romania's TLD servers.
Catalin Cosoi, chief security strategist at Romanian antivirus firm Bitdefender, explained: "The breach appears to have initially originated at the Romanian TLD, from where the compromised DNS records propagated to DNS cache servers. We believe that the RoTLD breach was carried in a similar manner as in the Pakistani hack. It is only a supposition, but all signs point to the same group."
Last week, defaced copies of Google, Yahoo!, Microsoft, eBay and Apple's Pakistan websites were shown to surfers, again as a result of a DNS hijack. Hackers latched onto vulnerabilities at PKNIC, a Pakistani domain name registrar, and altered records to pull off the attack, Softpedia reported.
Access to the affected Romanian sites was restored by Wednesday lunchtime, except Paypal.ro which proved difficult to reach in any case.
DNS systems translate human-friendly domain names, such as theregister.com, to internet addresses that routers and servers can understand and process. ®