More details have emerged on the operations of the Chinese state-sponsored threat actor known as APT41 and the links between its members, following the indictment of several alleged members of the group earlier this week.
Also tracked as Barium, Wicked Panda, Winnti, and Wicked Spider, the cyber-espionage group is said to have hacked over 100 organizations worldwide, including software and video gaming companies, governments, universities, think tanks, non-profit entities, and pro-democracy politicians and activists in Hong Kong.
APT41’s activity spans over more than a decade, with victims located in the United States, Australia, Brazil, Chile, Hong Kong, India, Indonesia, Japan, Malaysia, Pakistan, Singapore, South Korea, Taiwan, Thailand, and Vietnam.
This week, the United States made public two separate indictments returned by a federal grand jury in August 2019 and August 2020, charging Zhang Haoran and Tan Dailin, and Jiang Lizhi, Qian Chuan, and Fu Qiang, respectively.
In a report published on Thursday, cybersecurity firm Symantec revealed that it has tracked the activity of these hackers as belonging to two different groups, called Grayfly and Blackfly.
Grayfly activity, which has been observed in recent years, is associated with the indictment against Jiang, Qian, and Fu, who hold senior positions in a Chinese company named Chengdu 404, Symantec reports. The hackers launched numerous attacks on food, financial, government, healthcare, hospitality, manufacturing, and telecoms organizations in Asia, Europe, and North America.
Malware used by the threat actor includes Barlaiy/POISONPLUG and Crosswalk/ProxIP (Backdoor.Motnug), with many victims compromised through public facing web servers. Backdoor.Motnug, Symantec explains, offers remote access to the breached environment and also provides proxy access to hard-to-reach segments of the network.
Blackfly, Symantec says, has been active since at least 2010 and is mainly known for the targeting of video gaming companies. However, the hackers also attacked fintech, food, hospitality, materials manufacturing, media and advertising, pharmaceutical, semiconductor, and telecoms industries.
Malware used by the threat actor includes PlugX/Fast (Backdoor.Korplug), Winnti/Pasteboy (Backdoor.Winnti), and Shadowpad (Backdoor.Shadowpad). One specific artifact observed in the group’s attacks was the use of the names of security vendors when naming their malicious binaries.
Attacks associated with the Blackfly tools and tactics, Symantec reveals, can be attributed to two Malaysian nationals, Wong Ong Hua and Ling Yang Ching, who were arrested this month and who were also charged by U.S. authorities, for conspiring with the Chinese nationals. The two are also said to have worked with other hackers in campaigns against computer game companies.
The link between Grayfly and Blackfly, the security firm says, is drawn by two other Chinese nationals that the U.S. indicted as part of the APT41 group, namely Zhang Haoran and Tan Dailin. They allegedly worked at Chengdu 404 for a while, but also collaborated with the Blackfly actors for extra cash.
“Grayfly and Blackfly have been prolific attackers in recent years and, while it remains to be seen what impact the charges will have on their operations, the publicity surrounding the indictments will certainly be unwelcome among attackers who wish to maintain a low profile,” Symantec concludes.
In a report shared with SecurityWeek on Thursday, researchers with Secureworks note that APT41, which the security firm tracks as BRONZE ATLAS, is likely reusing old infrastructure in its operations. Two of the analyzed domains, they said, were associated with the group’s activity back in 2013, but continue to be in use.