MirrorFace, a China-aligned threat actor, has expanded its operations, targeting a Central European diplomatic institution. Their attack, called Operation AkaiRyū, used spear-phishing emails with lures related to Expo 2025 in Japan. This marks a shift from their traditional focus on Japan and highlights MirrorFace’s evolving tactics, including the use of a customized AsyncRAT variant executed in Windows Sandbox to evade detection. The group also deployed ANEL, a backdoor linked to APT10, and employed Visual Studio Code’s remote tunnels for stealthy access.
The group’s methods have advanced with new tools like HiddenFace, alongside the revived ANEL backdoor. MirrorFace’s improved operational security hinders investigations, with the deletion of malware tools, clearing Windows event logs, and running malware in Windows Sandbox. This stealth approach complicates incident analysis and allows the attackers to maintain persistence and avoid detection.
The use of ANEL also signals a shift in tactics, moving away from LODEINFO after a long period of inactivity.
Operation AkaiRyū overlaps with Japan’s Campaign C, which has targeted academia, think tanks, politicians, and media. MirrorFace’s attack chain includes DLL side-loading and spear-phishing attachments, delivering a loader named ANELLDR that decrypts and loads ANEL. The attack is notable for its strategic shift to use AsyncRAT within Windows Sandbox, significantly enhancing stealth and reducing the risk of detection.
MirrorFace has continued to refine its tactics and is now targeting European entities, showing its adaptability.
This expansion into Europe signals a broader targeting range for MirrorFace, with sophisticated post-compromise activities. The group’s use of Visual Studio Code, alongside traditional tools, reflects their evolving capabilities. Their focus on Expo 2025 in Japan demonstrates the group’s ongoing interest in Japanese-related events. Despite the increasing complexity of their operations, the full scope of MirrorFace’s activities remains difficult to piece together due to its robust operational security.
