On the day Adobe patched two of the Flash Player zero-day vulnerabilities uncovered following the Hacking Team breach, FireEye researchers noticed that one of the flaws had been used in an attack aimed at organizations in Japan.
Italy-based surveillance software company Hacking Team has suffered a data breach and hackers leaked a total of 400GB of data stolen from the spyware maker’s systems. Researchers discovered exploits for several unpatched vulnerabilities after analyzing the Hacking Team leak, including Windows kernel, Microsoft Office, and Adobe Flash Player exploits.
Malicious actors started exploiting the first Flash Player zero-day (CVE-2015-5119) before Adobe managed to roll out a patch. This bug was leveraged by both cybercriminals and advanced persistent threat (APT) actors. Trend Micro reported that this particular flaw had been exploited in attacks against users in Korea and Japan even before the Hacking Team breach came to light.
The other two Flash Player bugs found in the Hacking Team leak are CVE-2015-5122 and CVE-2015-5123. Cybercrooks started integrating CVE-2015-5122 into exploit kits shortly after its existence was revealed.
On July 14, the day on which Adobe released security updates to patch the two vulnerabilities, researchers at FireEye spotted a campaign targeting Japanese organizations. The attackers launched a watering hole attack involving at least two legitimate Japanese websites that they had compromised.
The attackers hijacked the websites of Japan’s International Hospitality and Conference Service Association (IHCSA) and cosmetics company Cosmetech. Exploits planted on these sites delivered a piece of malware known as SOGU to visitors running vulnerable versions of Flash Player.
SOGU is a backdoor often used by Chinese threat actors in their operations. The sample used in the attacks observed by FireEye had been compiled on July 13 and its binary was designed to look like a legitimate file from security firm Trend Micro.
“The threat group likely used Trend Micro, a security software company headquartered in Japan, as the basis for the fake file version information deliberately, given the focus of this campaign on Japanese organizations,” FireEye explained in a blog post.
According to researchers, the campaign made at least two victims over a two-day period. It’s unclear how the victims were lured to the watering hole websites, but FireEye believes phishing emails might have been used.
The use of SOGU malware and the dissemination method has led experts to believe that a Chinese APT group is behind the operation. However, FireEye has been unable to determine which group is responsible.
“The Japanese economy’s technological innovation and strengths in high-tech and precision goods have attracted the interest of multiple Chinese APT groups, who almost certainly view Japanese companies as a rich source of intellectual property and competitive intelligence,” FireEye said. “The Japanese government and military organizations are also frequent targets of cyber espionage. Japan’s economic influence, alliance with the United States, regional disputes, and evolving defense policies make the Japanese government a dedicated target of foreign intelligence.”