SecTor 2025 | How Adversaries Beat User-Mode Protection Engines for Over a Decade

Why It Matters

User‑mode evasion has become the dominant post‑exploitation vector, forcing vendors to rethink endpoint designs and prompting regulators to scrutinize kernel‑level protections.

Key Takeaways

• 27 evasion methods classified into Hook Evasion, Argument Forgery, Engine Disarming
• User-mode attacks outpace kernel-level defenses in recent years
• Research covered 55 sources and malware like Emotet, Hive, Winnti
• Detection guidance offers runtime and forensic indicators for responders

Pulse Analysis

The fallout from the July 2024 global IT outage sparked a regulatory push to ban kernel‑level components in endpoint security products. While many vendors rushed to redesign their solutions, a substantial portion of the market still relies on user‑mode detection engines for performance and compatibility reasons. This environment created a fertile ground for attackers to refine techniques that slip past user‑mode defenses, prompting a need for comprehensive research into the breadth and depth of these evasion methods.

Misgav’s investigation combined public repositories such as SysWhispers and FireWalker with reverse‑engineering of notorious malware families—including Emotet, SmokeLoader, and Winnti—to map the evolution of user‑mode evasion over more than ten years. The study cataloged 27 unique techniques, grouped into Hook Evasion (subverting API hooks), Argument Forgery (manipulating input parameters), and Engine Disarming (directly disabling security modules). By ingesting over 55 data sources, the team demonstrated that user‑mode evasion now eclipses classic code‑injection tactics, making it the most prolific post‑exploitation strategy in the current threat landscape.

For security practitioners, the findings underscore the urgency of augmenting user‑mode defenses with layered detection. The briefing introduced runtime signatures—such as anomalous DLL loading patterns—and forensic artifacts like altered registry keys that can reveal evasion attempts. Incident responders and threat hunters can leverage these indicators to improve detection coverage, while vendors may need to integrate kernel‑assisted safeguards or hybrid models to stay ahead of adversaries. As regulators continue to evaluate endpoint security architectures, the balance between performance, privacy, and robust protection will shape the next generation of defense solutions.

Original Description

Following the largest global IT outage in history in July 2024, many took to the public stage advocating to prohibit endpoint security vendors from deploying kernel-based components, even prompting regulators to weigh in. That launched an effort to evaluate the impact of the proposed design shift, as many endpoint-oriented security solutions, from different malware analysis tools to various commercial products (like AVs, EDRs and sandboxes), already include user mode-based engines.

The research started with examining open-source projects and publications such as SysWhispers and FireWalker, and continued by analyzing and reverse-engineering malware families of all types in the wild, including infamous names like Emotet, SmokeLoader, HijackLoader, FormBook, DarkGate, Hive ransomware and Winnti, among others. Over 55 different data sources were ingested, all in all, mapping the entire threat landscape and tracking the evolution of adversaries for more than a decade. Curating the ultimate collection on the subject yielded in-depth understanding and insights into attackers' tradecraft and made it clear that this is the most prolific post-exploitation technique yet, surpassing even code injection methods.

This session will explore all 27 unique methods which security researchers and malware authors have developed to beat user mode-based protection engines, cataloged under 3 main tactics: Hook Evasion, Argument Forgery and Engine Disarming. The trade-offs of the various methods will be highlighted as well. In addition, the session will include detection schemes, focusing on runtime and forensic indicators, to aid malware researchers, incident responders, threat hunters and detection engineers tackling these issues.

By:

Omri Misgav | Security Researcher, Independent

Presentation Materials Available at:

https://blackhat.com/sector/2025/briefings/schedule/#evading-in-plain-sight-how-adversaries-beat-user-mode-protection-engines-for-over-a-decade-45850