Turkish banks fend off cyberattacks, some transactions hit

Ahmet Can – ISTANBUL

A number of Turkish banks reported serious disruption in online operations and credit card transactions Dec. 25, as hackers stepped up a series of cyberattacks seen in the country over the past week.

Officials at several Turkish banks including Iş Bank, Garanti and state lender Ziraat Bank confirmed the attacks, saying they had caused intermittent disruption, Reuters reported. Bank shares were unmoved by the news. 

“The attacks are serious,” said Onur Oz, a spokesman for Internet provider Turk Telekom. “But the target is not Turk Telekom. Instead, banks and public institutions are under heavy attack,” he said. 

“A majority of Turkish institutions use Turk Telekom as the service provider, therefore we are the ones doing the defense against these attacks.” 

Some 50,000 computers in Turkey unintentionally contributed to attacks without the knowledge of their owners, according to experts who commented on the attacks that intensified on banks for two days. 
The technique used by Anonymous, the alleged hacker group behind the cyberattack, is known as a Denial of Service Attack (DDoS), experts said. 

A DDoS is basically a bid to overrun the user capacity of a website, blocking it due to a high traffic. Hackers use software hidden in thousands of computer to direct such traffic to targeted websites. This technique turns unaware users’ computers into “zombie” machines to carry out the attack. 

Former inspections by the Telecommunications Directorate (TİB) had revealed that Anonymous had uploaded such software in computers in Turkey, citing the number of such infected computers at 50,000. Local computers can sustain an attack even in cases that access from abroad is cut. Turkey hosts the fourth highest numbers of such zombie computers, following the U.S., India and Japan, according to Trend Micro figures. 

Local media have suggested that the bombardment of public and financial websites could be coming from Russia, after a sharp worsening of tensions between Moscow and Ankara, or staged by Anonymous. However, no clear evidence has emerged, and authorities have avoided pointing the finger. 

A government cyber security unit was taking precautions and the incident was under control, Transport Minister Binali Yildirim said earlier this week. He did not comment specifically on the targeting of banks, and his ministry was not available for comment on Dec. 25. 

“These attacks began two weeks ago but have intensified over the past two days,” said Burak Atakanı, a network specialist from Istanbul Technical University.
 
He said that the service provider used by some universities, police academies and the research department of the military had also come under attack. 

Nic.tr, a non-government body that administers addresses for websites using Turkey’s “.tr” domain, including ministries, the military, banks and many commercial sites, said earlier this week that the attacks originated from “organized sources” outside Turkey. 

Turkey incensed Russia last month by shooting down a Russian military plane near the Syrian border, and Moscow has retaliated with economic sanctions. In the past, countries such as Estonia and Georgia have suffered cyberattacks emanating from Russia after incurring Moscow’s anger. 

Reuters sought comment from the Russian foreign ministry, but none was immediately available. 

Separately, the Anonymous hacking group posted a video over the weekend on YouTube, which has since been removed, saying cyberattacks would continue if Turkey “doesn’t stop supporting” Islamic State of Iraq and the Levant (ISIL), giving credit to Russian President Vladimir Putin’s claims that are categorically ruled out by Turkish authorities.