Description

Earth Estries, a China-linked cyber threat actor, has been observed using a previously undocumented backdoor called GHOSTSPIDER to target telecommunications companies across Southeast Asia. Trend Micro, which has labeled the group as an advanced persistent threat (APT), also reported the use of another cross-platform backdoor, MASOL RAT, found on Linux systems within Southeast Asian government networks. In total, Earth Estries is believed to have compromised over 20 organizations across various sectors, including telecommunications, technology, government, and non-profits, with victims located in over a dozen countries, such as the U.S., India, Vietnam, and Brazil. Active since at least 2020, Earth Estries shares similarities with other Chinese threat groups like FamousSparrow, GhostEmperor, Salt Typhoon, and UNC2286. The group has targeted a wide range of industries and government entities in regions including the U.S., Asia-Pacific, the Middle East, and South Africa. A recent report revealed that Earth Estries has infiltrated over a dozen telecom companies in the U.S., with up to 150 victims identified. The group's initial access to victim networks is typically gained by exploiting known vulnerabilities in widely used software such as Ivanti Connect Secure, Fortinet FortiClient EMS, Sophos Firewall, and Microsoft Exchange Server. Once inside, Earth Estries deploys custom malware like Deed RAT, Demodex, and GHOSTSPIDER to maintain persistent access and conduct ongoing cyber espionage activities. These attacks allow the group to gather sensitive information from compromised entities over extended periods. Trend Micro researchers have highlighted that Earth Estries operates with a high level of organization, with different sub-groups handling specific tasks, such as infrastructure management and malware deployment. GHOSTSPIDER, for example, uses a custom protocol secured with Transport Layer Security (TLS) to communicate with the attacker’s infrastructure and can download additional modules to extend its capabilities. This multi-layered approach makes it difficult to detect and mitigate the group’s activities.