Description

An undisclosed advanced threat actor named 'Blackwood' has been identified by cybersecurity firm ESET, using sophisticated malware named NSPX30 in cyberespionage campaigns targeting companies and individuals. Blackwood has been active since at least 2018, leveraging the NSPX30 malware, which is rooted in a backdoor codebase from 2005. The activities of this threat actor align with Chinese state interests, according to ESET. Blackwood's targets are primarily in China, Japan, and the United Kingdom. The NSPX30 malware is delivered through the update mechanisms of legitimate software such as WPS Office, Tencent QQ instant messaging platform, and the Sogou Pinyin document editor. Blackwood utilizes adversary-in-the-middle (AitM) attacks to intercept traffic generated by NSPX30, concealing its activities and hiding command and control (C2) servers. ESET researchers note that Blackwood might share access with other Chinese APT groups, as they observed multiple actors, including Evasive Panda, LuoYu, and LittleBear, targeting the system of one company. NSPX30, evolving from the 2005 backdoor 'Project Wood,' exhibits a multistage architecture with advanced features, including extensive UAC bypassing capabilities, packet interception to hide infrastructure, and mechanisms to evade detection by Chinese anti-malware tools. NSPX30's primary function is to collect information from compromised systems, including files, screenshots, key presses, hardware and network data, and credentials. An interesting aspect of Blackwood's tactics is delivering NSPX30 by intercepting update requests of legitimate software, distinguishing it from traditional supply-chain compromises. The exact mechanism enabling Blackwood to intercept traffic remains unknown, with speculation about the use of implants in target networks, possibly on vulnerable appliances like routers or gateways. ESET's report provides detailed insights into NSPX30's technical aspects and indicators of compromise for defenders.