A data-stealing malware program on North Korea’s official news site discovered earlier this year appears to have been planted there by external attackers -- not the government, as some originally had assumed.
Security researchers at Kasperksy Labs recently reviewed the Korea Central News Agency (KCNA) website and discovered that the malware is still active on the site’s main page. However, a closer examination of the illicit software suggests that the site’s developers did not plant it there.
Instead, the malware’s trigger mechanism, system requirements, and its similarities with software used in the more recent Darkhotel cyber espionage campaign point toward an external actor, says Juan Guerrero-Saade, senior security researcher with Kaspersky’s Global Research and Analysis Team.
In addition, the KCNA site itself was vulnerable to a cross-site scripting flaw right around the time the malware first surfaced on the site. So anyone could have planted the malware, not just the site’s government-sponsor.
Contrary to what many may have assumed, the malware also appears designed more to infect systems belonging to users in North Korea rather than visitors to the KCNA website from outside the country, Guerrero-Saade says.
“Because of what happened at Sony and because this was a North Korean site, many people had no trouble assuming North Korean involvement,” when the malware was originally discovered, he said.
A security researcher writing for InfoSecOtter (the site is currently unavailable) first reported news of the North Korean website being rigged with malware in January. The code, disguised as a Flash Player update, was apparently designed to infect systems of people visiting the website.
According to Guerrero-Saade, users attempting to view pictures or video contained in a section of KCNA’s front page are presented with a gif urging them to install Flash Player. Those clicking on the link are directed to a malicious zip file that drops two executable files masquerading as Flash Player updates on the user’s system.
Contrary to original perceptions, the malware does not infect all systems that visit the site. Instead, it only infects systems running Flash Player 10 or older versions. It ignores all computers featuring more modern versions of Flash Player. This suggests that the attackers behind the malware are targeting extremely outdated Windows PCs, such as those likely being used inside North Korea, Guerrero-Saade says.
Once installed on a computer, the malware gathers system information and passes it on to one of three command and control servers. It also scans removable drives and network shares for executable files to infect. The malware can be remotely configured to collect any information attackers want from the infected system.
Guerrero-Saade says the malware hosted on KCNA bears many similarities to the Darkhotel campaign. Just like Darkhotel, the KCNA info-stealer is highly selective about the systems it infects. At the same time, both malware tools are also designed to spread indiscriminately through other means. Both pieces of malware are designed to steal mostly the same information and maintain the stolen data in very similar formats. Both data stealers also use spoofed Flash Player updates and share several similarities in code.
Systems infected with the KCNA info stealer have been detected in China, Malaysia, Russia, South Korea, and Taiwan.
Guerrero-Saade says he is not sure why the malware has not been removed from the North Korean website, even though it has been several weeks since its presence was first disclosed. “It is definitely curious,” he says.