A three-year-old cyber operation is using a mix of social engineering, Microsoft Windows vulnerabilities and basic stenography to target government, military and industry officials in Taiwan and the Philippines, according to Trend Micro.
In a new report, the security firm revealed the ongoing attacks – which it dubbed ‘Operation Tropic Trooper’ – go back to 2012, but the malware the attackers are using shares traits with samples Trend Micro first examined in 2011. Between March and May of this year, 62 percent of the malware infections have targeted Taiwanese organizations, while the remaining 38 percent have hit entities in the Philippines. In Taiwan, the targets have included government ministries and heavy industries, while the targets in the Philippines have been in the military.
While Trend Micro did not identify the actors behind the attacks, researchers were able to pinpoint command and control servers in four countries: Taiwan (home to 43 percent of the servers), Hong Kong (14 percent), U.S. (36 percent) and the United Arab Emirates (seven percent).
“This latest attack relied on two of the most-exploited Windows vulnerabilities to date—CVE-2010-3333 and CVE-2012-0158—to infiltrate the target networks,” blogged Kervin Alintanahin, threats analyst at Trend Micro. “This suggests that the organizations were running on unpatched, vulnerable systems that made them more susceptible to threats.”
“Aside from exploiting those vulnerabilities, the threat actors used basic steganography,” the researcher continued. “This means they were able to conceal malicious code in JPEG files popularly used as Windows XP wallpapers. Steganography, although not a new cybercriminal tactic, is not commonly used in targeted attacks.”
The attackers may have chosen this approach because of the continued use of XP systems in Taiwan and the Philippines despite the operating system having reached its end-of-life, Alintanahin noted. There is also a chance the threat actors have used steganography because they either still use Windows XP themselves or have in-depth knowledge of it, the researchers added.
The attack starts with emails laced with a malicious attachment. Opening the documents leads to the execution of malware that downloads an image file to the system, according to Trend Micro.
“Closer inspection of the downloaded image file reveals that it uses steganography to hide the malicious content,” the researcher explained. “It will decrypt executable files in memory and will not save it to the disks. These files are installers and will drop the backdoor BKDR_YAHAMAM. With the backdoor’s capabilities of downloading, uploading, and creating a remote shell, it can easily conduct the next phase of its attack which is to find other targets within its reach.”
“Operation Tropic Trooper is not highly sophisticated,” Alintanahin noted. “But the fact that it has attained some degree of success and has managed to infiltrate crucial organizations in both Taiwan and the Philippines shows the urgent need for targeted entities to rectify their shortcomings in terms of security. Knowing that attackers are still using old techniques and exploiting known vulnerabilities will make it easier for the targeted organizations to pinpoint and fix security gaps in their networks.”
The Trend Micro report can be read here.