Cybersecurity researchers from Check Point Research (CPR) have disclosed a sophisticated phishing campaign orchestrated by the Russian-linked cyber-espionage group APT29, also known as Cozy Bear or Midnight Blizzard. Since January of this year, European diplomatic entities, including Ministries of Foreign Affairs and foreign embassies, have been targeted by APT29 through deceptive phishing emails. These emails are cleverly disguised as invitations to wine-tasting events and are designed to lure recipients into a trap. Embedding malicious links, the emails come from domains like bakenhof[.]com and silry[.]com and use enticing subject lines such as “Wine Event” or “Diplomatic Dinner.” When recipients click on the embedded links, they are redirected to legitimate ministry websites or prompted to download a zip file named wine.zip, containing the GRAPELOADER malware.
The GRAPELOADER Malware and Its Tactics
GRAPELOADER represents a notable advancement in stealth and persistence, employing various sophisticated techniques to evade detection and maintain its presence within the targeted systems. The malware incorporates dynamic API resolving, DLL unhooking, and memory-based shellcode execution to circumvent standard security tools. Once installed, GRAPELOADER modifies registry settings to ensure its execution even after system reboots. It fingerprints the host system, gathering basic system information which it then sends to a Command and Control (C2) server to receive further instructions and facilitate the delivery of additional payloads.
Furthermore, GRAPELOADER supports the deployment of other malware, including an updated variant of WINELOADER known as vmtools.dll. This updated variant employs even more sophisticated evasion techniques, such as code mutation and structural obfuscation. It utilizes RC4-based encryption to secure communication with the C2 server and improves unpacking routines by leveraging DLL side-loading methods. These advanced tactics make detection and mitigation of the malware exceedingly challenging, as it collects and encrypts environment information before transmitting it back to the C2 infrastructure for further exploitation.
Recurring Themes and Evolution of APT29’s Campaigns
The latest campaign by APT29 echoes a recurring pattern observed in previous WINELOADER campaigns from last year, reflecting the group’s established tactics in cyber espionage. Their methods indicate a consistent evolution in the sophistication of their malware, constantly adapting to achieve persistence and elude even the most advanced cybersecurity defenses. This relentless drive for improvement underscores the group’s significant capabilities and the persistent threat they pose to diplomatic entities. APT29’s involvement in high-profile incidents, such as the SolarWinds supply chain attack, further highlights their expertise and the need for heightened vigilance.
The group’s strategy of using familiar themes, such as wine-tasting event invitations, showcases their ability to exploit human behavior and social engineering techniques effectively. By blending legitimate events with malicious intent, APT29 successfully deceives their targets, leading to the execution of their sophisticated malware. The dual combination of phishing and advanced malware ensures a multi-layered attack approach, making it difficult for traditional security measures to counteract their efforts.
Implications and Future Considerations
GRAPELOADER marks a significant advancement in stealth and persistence, using advanced methods to avoid detection and remain in targeted systems. This malware employs dynamic API resolving, DLL unhooking, and memory-based shellcode execution to bypass typical security tools. Once it infiltrates a system, GRAPELOADER alters registry settings to ensure it runs even after reboots. It identifies the host system, gathering basic information to send to a Command and Control (C2) server for further instructions and to facilitate additional payload delivery.
Moreover, GRAPELOADER aids in deploying other malware, including an updated version of WINELOADER called vmtools.dll. This version uses even more advanced evasion techniques like code mutation and structural obfuscation. It employs RC4-based encryption for secure communication with the C2 server and enhances unpacking routines through DLL side-loading methods. These advanced techniques make detection and mitigation extremely difficult, as it collects and encrypts environmental information before sending it back to the C2 infrastructure for further exploitation.
