Among the plethora of advanced attacker tools that exemplify how threat actors continuously evolve their tactics, techniques, and procedures (TTPs) to evade detection and maximize impact, PipeMagic, a highly modular backdoor used by Storm-2460 masquerading as a legitimate open-source ChatGPT Desktop Application, stands out as particularly advanced.

Beneath its disguise, PipeMagic is a sophisticated malware framework designed for flexibility and persistence. Once deployed, it can dynamically execute payloads while maintaining robust command-and-control (C2) communication via a dedicated networking module. As the malware receives and loads payload modules from C2, it grants the threat actor granular control over code execution on the compromised host. By offloading network communication and backdoor tasks to discrete modules, PipeMagic maintains a modular, stealthy, and highly extensible architecture, making detection and analysis significantly challenging.

Microsoft Threat Intelligence encountered PipeMagic as part of research on an attack chain involving the exploitation of CVE-2025-29824, an elevation of privilege vulnerability in Windows Common Log File System (CLFS). We attributed PipeMagic to the financially motivated threat actor Storm-2460, who leveraged the backdoor in targeted attacks to exploit this zero-day vulnerability and deploy ransomware. The observed targets of Storm-2460 span multiple sectors and geographies, including the information technology (IT), financial, and real estate sectors in the United States, Europe, South America, and Middle East. While the impacted organizations remain limited, the use of a zero-day exploit, paired with a sophisticated modular backdoor for ransomware deployment, makes this threat particularly notable.

This blog provides a comprehensive technical deep dive that adds to public reporting, including by ESET Research and Kaspersky. Our analysis reveals the wide-ranging scope of PipeMagic’s internal architecture, modular payload delivery and execution mechanisms, and encrypted inter-process communication via named pipes.

The blog aims to equip defenders and incident responders with the knowledge needed to detect, analyze, and respond to this threat with confidence. As malware continues to evolve and become more sophisticated, we believe that understanding threats such as PipeMagic is essential for building resilient defenses for any organization. By exposing the inner workings of this malware, we also aim to disrupt adversary tooling and increase the operational cost for the threat actor, making it more difficult and expensive for them to sustain their campaigns.