By Kim Tong-hyung
Staff Reporter

Korean computer users must beware of malicious code writers who are getting increasingly creative and prolific in trying to make an illicit buck, a local computer vaccine maker said.

According to a report released Thursday by AhnLab, a total of 10,580 spyware and other malicious codes were newly found in the country during the first-half of this year, more than double the 4,376 found during the same period of 2007.

A Trojan horse, notorious for its use of installing backdoor programs, was the most common type of malware found here, with 6,196 programs reported during the Jan.-June period, nearly triple the 2,293 found in 2007.

The number of spyware programs, which could take partial control of an affected computer and collect personal information, install additional software and even change computer settings, was reported at 2,285, approximately double from 2007's 1,070.

``It is becoming easier to write malicious codes, and tools that allow those programs to automatically attack systems are continuing to be produced and shared," said Cho Si-haeng, director of AhnLab's security response division.

``The attackers using these programs are becoming more organized and are aiming to make illicit earnings by targeting a certain system or organization," he said.

Cho also said that the emergence last month of ARP (address resolution protocol) spoofing, which allows an attacker to intercept traffic by modifying the Internet protocol address of a computer and forward unwanted programs, remains a serious concern. Other trends include the increase of sphere phishing, or e-mail spoofing fraud aimed at accessing confidential information, and the increase of SQL injection attacks, which exploits security vulnerabilities in computers using search engines.

The expansion of the blogosphere is also giving new ideas to attackers looking to spread their malware. Some malicious code writers are creating Weblogs that gather visitors by using popular search words on portals and then use the traffic to spread malware, Cho said.

``There are even cyber black markets where malicious codes are shared, which shows that these activities now represent organized crime" Cho said.

thkim@koreatimes.co.kr