When cybersecurity researchers began dissecting a ransomware strain now known as Reynolds, they found something that set it apart from many recent threats. Embedded directly within the malware was a mechanism designed not to steal data or encrypt files, but to neutralize the very security systems meant to stop it.
The technique, known as “bring your own vulnerable driver,” or BYOVD, exploits flaws in legitimate, digitally signed software drivers. In the Reynolds case, attackers bundled a vulnerable driver from NsecSoft inside the ransomware payload itself, allowing the malware to terminate endpoint detection and response tools before they could raise alarms.
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Researchers from Broadcom’s Symantec and Carbon Black threat-hunting teams said this integration marked an evolution in ransomware design. Traditionally, attackers deploy a separate tool to disable security software before delivering ransomware. Here, that step was folded into a single package, reducing noise and shortening the window for detection.
An Old Technique, Refined for Scale
BYOVD attacks are not new. Over the past decade, ransomware groups have repeatedly abused flawed drivers to gain elevated privileges on Windows systems. But embedding the driver directly into the ransomware represents a refinement aimed at scale and efficiency.
The vulnerable driver used in the Reynolds campaign, NSecKrnl, carries a publicly documented flaw that allows arbitrary process termination. Once loaded, the driver can be weaponized to shut down security products from major vendors, including Avast, CrowdStrike, Palo Alto Networks, Sophos and Symantec.
Security analysts noted that similar approaches had surfaced before, including in a Ryuk ransomware attack in 2020 and in a lesser-known campaign tied to a group called Obscura in 2025. What distinguishes Reynolds is the degree to which defense evasion and payload delivery are fused into a single operation, reducing the need for affiliates to customize attacks.
A Broader Surge in Ransomware Sophistication
The appearance of Reynolds comes amid a period of rapid experimentation in the ransomware ecosystem. Threat actors are increasingly professionalized, borrowing tactics from one another and refining them for reliability.
Recent campaigns have relied on phishing emails with Windows shortcut files to deliver ransomware capable of operating entirely offline. Others have abused legitimate virtual infrastructure providers to host malware at scale, complicating takedown efforts. Some groups now offer affiliates services resembling corporate consultancies, complete with “data audits” and negotiation scripts designed to maximize extortion payouts.
At the same time, established names have re-emerged with more advanced tooling. A new iteration of LockBit, for example, has expanded beyond Windows to target Linux and virtualized environments, adding wiper components and memory-only execution to limit forensic traces.
Industry data suggests that these innovations are translating into volume. Ransomware groups claimed thousands of attacks globally last year, while incidents focused solely on data theft — rather than encryption — rose sharply as criminals tested alternative forms of leverage.
Security at the Intersection of Software and Trust
For defenders, the Reynolds campaign underscores a persistent dilemma: modern security tools rely on trust in signed software, the same trust attackers exploit when abusing legitimate drivers. Because these components are real and often widely used, blocking them outright can disrupt normal operations.
Researchers also pointed to signs of patience in the Reynolds operation. Evidence suggests that attackers had established a foothold on at least one victim network weeks before deploying the ransomware, using a side-loaded loader and later a remote access tool to maintain persistence.
Cybersecurity experts say such tactics reflect a broader reality. As organizations harden their defenses, ransomware groups are shifting from blunt-force attacks to quieter, more surgical methods that blend into normal system behavior.
The result is an arms race less defined by flashy exploits than by subtle abuses of trust — one in which the line between legitimate software and malicious activity continues to blur.
About the author — Suvedita Nath is a science student with a growing interest in cybercrime and digital safety. She writes on online activity, cyber threats, and technology-driven risks. Her work focuses on clarity, accuracy, and public awareness.
