A malware analysis report published on Monday by the U.S. Department of Defense, the Cybersecurity and Infrastructure Security Agency (CISA), and the FBI officially attributes a piece of malware named Taidoor to threat actors sponsored by the Chinese government.
Taidoor, also tracked by some as Taurus RAT, has been around since at least 2008. In 2012, Trend Micro reported that the malware had been used in targeted attacks aimed at government organizations in Taiwan. Taidoor was used at the time by threat actors to operate a shell on compromised devices, and download and upload files.
In 2013, FireEye published a report on Taidoor being used in cyber espionage campaigns aimed at government agencies, think tanks and companies, particularly ones with an interest in Taiwan.
While there was some evidence at the time suggesting that China was behind the attacks involving Taidoor, the U.S. government has now officially said that the malware, which it describes as a remote access trojan (RAT), is “used by Chinese government cyber actors.”
“FBI has high confidence that Chinese government actors are using malware variants in conjunction with proxy servers to maintain a presence on victim networks and to further network exploitation,” the report reads.
The United States Cyber Command has uploaded four Taidoor samples to Google’s VirusTotal service. While two of the samples are currently detected by over 30 of the 59 anti-malware engines on VirusTotal, two of them are only detected by 9 engines.
The report published by the U.S. agencies includes technical details on how the malware works, as well as information that can be used by organizations to identify and block attacks involving Taidoor.
USCYBERCOM started sharing malware samples with the cybersecurity industry in November 2018. A majority of the samples it has shared to date have been linked to North Korean threat actors, and some have been attributed to Russian and Iranian hacking groups. It appears that the Taidoor samples are the first Chinese malware samples shared by the agency.
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