Continuous hacker attacks have managed to block the online population census in Bulgaria, which began on Tuesday. On the third day, the system was down due to another large-scale denial-of-service (DoS) attack.

Two of the attacks committed in the first days could be traced to Chinese and Swedish IP addresses. On Wednesday, the National Statistical Institute (NSI) temporarily restricted access to the site and all its systems to prevent data leaks.

The institute’s chairman, Sergei Tsvetarski, is set to speak to the Bulgarian parliament about problems in the system.

Democratic Bulgaria MP Ivaylo Mirchev, who has experience in IT business, has criticised the NSI for failing to implement basic activities to protect the national census platform from DoS attacks.

“The NSI had 10 years to prepare for this moment. In the last six years in the country, we have witnessed a series of attacks on the technological infrastructure of many state institutions. It turns out that no one in the NSI has drawn conclusions from this,“ said Mirchev.

Bulgarian cybersecurity expert Spas Ivanov told Nova TV that “the goal of blocking the census system is most often political”.  According to him, access to the institute’s website should be restricted to Bulgarian IP addresses as this would reduce attacks with fake access requests from China, Russia and Argentina.

Dozens of Bulgarians have already lodged complaints with the national ombudsman over suspicions of endangered rights in the census procedure.

Two years ago, the Bulgarian tax agency allowed the theft of personal data of nearly five million Bulgarians, foreigners with business in the country and companies.

(Krassen Nikolov | EURACTIV.bg)