DDoS Attacks Turn Into Lethal Weapon
By Kim Tae-gyu
Staff Reporter
From the perspective of cyber terrorists, the distributed denial-of-service (DDoS) attacks have been regarded as a sword too blunt to inflict a deep wound on their targets.
As its name indicates, the DDoS attackers try to overload specific Web sites with massive amount of simultaneous traffic via zombie computers. It's like many rogues continuing to hit the F5 key to monopolize access to the targeted Internet sites.
It is an online equivalent of vandalism just like graffiti on the wall ― annoying but not destructive. As soon as the bad guys are tired of pressing the F5 key, the Web site will immediately recover.
However, the once-simplistic online extortion attacks could turn into a lethal weapon as demonstrated by the recent wave of the DDoS attacks suspected of originating from North Korea.
The reason: A flurry of businesses moved from the actual world to the virtual one. Hence, slamming shut the door of an Internet site itself poses a great threat to the overall system.
``Think of banks. With so many transactions carried out online, the denial of access to their Web sites causes substantial damages to the daily life of people and the overall economy,'' said an official at the state-run Korea Information Security Agency.
``Imagine Web sites of unprepared financial firms shut down at the same time. You can hardly do anything and the losses would be awful,'' he said.
Most domestic banks were attacked since last Saturday, including Shinhan Bank, Korea Exchange Bank, Kookmin Bank, Woori Bank and Industrial Bank of Korea.
End users were inconvenienced by slow connection speeds when trying to connect to banks' Web sites, although they did not go down completely as the protection system worked.
Zombie computers
Beneath of the DDoS attacks lurk zombie computers, which are typically owned by innocent citizens but are remote-controlled by a handful of bad guys.
The Seoul administration thinks that tens of thousands of zombie computers were deployed to harass scores of Web sites in Korea and the United States.
Zombie PC holds various kinds of computer viruses, which are usually installed without the knowledge of their owners.
In order to avoid becoming a zombie PC, AhnLab recommends the users of desktops or laptops remain alert against malicious codes ready to infect unsuspecting folks.
``You should update your operating system to the latest patch level as well as change the password to Internet accounts. Just don't synchronize ID and password,'' AhnLab Vice President Cho Si-haeng said.
``In particular, you should not open an attached file of a suspicious e-mail. In addition, you must ignore any unwarranted notes in the instant messaging services,'' he said.
To check whether the computer is already infected to become a zombie PC, Cho recommended running an anti-virus program, which can be downloaded from AhnLab's Web site.
The vaccine, available at www.ahnlab.com, is free of charge for both individuals and corporate users. AhnLab is the country's No. 1 developer of anti-virus programs.