Security researchers have revealed a ransomware operation known as Prinz Eugen that employs an unusual file-encryption strategy designed to increase pressure on victims. According to an investigation by ThreatDown, Malwarebytes' enterprise security division, the malware gives priority to files that have been modified most recently, focusing its efforts on data that organizations are most likely to rely on for day-to-day operations.
Researchers describe the actors behind Prinz Eugen as highly interactive intruders who rely on direct involvement throughout the attack process rather than fully automated deployment methods. Instead of depending on large-scale ransomware affiliate networks, the group appears to conduct attacks manually, using legitimate administration tools and built-in system utilities to move through victim environments and maintain access.
Evidence collected during incident response investigations suggests that attackers may initially gain entry through compromised Remote Desktop Protocol (RDP) credentials. After securing access, operators manually retrieve and launch the ransomware payload, identified as servertool.exe. In one investigated intrusion, researchers observed the use of the RemotePC remote management platform, alongside the creation of a backdoor administrator account that allowed the attackers to retain access to the compromised environment.
ThreatDown noted that Prinz Eugen does not currently appear to operate under the ransomware-as-a-service model that has become common across the cybercriminal ecosystem. Researchers found no indication that the group's operators are actively recruiting affiliates or distributing their malware to external partners. Instead, available evidence points to a more centralized operation in which attacks are carried out directly by the threat actors themselves.
Although the group's data-leak platform presently displays only three victims, researchers believe the actual number of affected organizations is higher. Information gathered during investigations indicates that multiple organizations have experienced incidents linked to the ransomware. Depending on the attack, victims may face file encryption, data theft, or a combination of both. Security researchers have identified at least five organizations impacted by the operation, including an incident involving Standard Bank, where attackers reportedly demanded a ransom payment of one Bitcoin. The demand was ultimately rejected.
One of the most distinctive characteristics of Prinz Eugen is its approach to selecting files for encryption. Analysis of the malware revealed that it processes files according to modification time, encrypting the most recently changed data before moving to older content. When several files share the same timestamp, the malware follows alphabetical order to determine which file is processed next.
Researchers believe this strategy is intended to maximize operational disruption. Files that have been edited recently are often associated with ongoing business activities, active projects, financial records, or other information that employees depend on regularly. By rendering this data inaccessible first, attackers can create immediate pressure on organizations to engage with extortion demands.
Technical analysis further showed that the ransomware scans directories recursively without imposing depth restrictions. Unlike some ransomware families that avoid certain locations or system folders, the examined Prinz Eugen sample applies very few limitations. The malware attempts to encrypt virtually every accessible file it encounters, excluding only files that already carry the .prinzeugen extension, which is added to data after encryption has been completed.
The encryption mechanism itself incorporates multiple modern cryptographic components. Researchers found that the ransomware uses the ChaCha20-Poly1305 algorithm together with a 32-byte master key. Each targeted file receives its own randomly generated initialization vector, while key generation and derivation processes rely on Argon2id, SHA-256, and HKDF-SHA256. Data is encrypted in 1 MB segments, and SHA-256 hashing is used to verify file integrity throughout the process.
Investigators also identified a safeguard built into the malware's deletion routine. When operators use the – delete option, the ransomware removes original files only after confirming that the encrypted version can be successfully decrypted. This verification step reduces the likelihood of accidental data destruction that could undermine the attackers' leverage over victims.
Beyond encrypting files, Prinz Eugen incorporates measures intended to frustrate forensic investigations. Researchers observed that the malware overwrites encryption keys with zero values once they are no longer needed, triggers garbage collection routines to remove remaining traces from memory, and then attempts to delete itself from disk. These actions are designed to make post-incident analysis and key recovery efforts more difficult.
Another noteworthy aspect of the ransomware is the absence of conventional extortion artifacts. The analyzed sample contains no functionality for dropping a ransom note onto infected systems, nor does it alter the victim's desktop wallpaper to display payment instructions. While such techniques have historically been common among ransomware groups, ThreatDown researchers noted that some organized operations are increasingly shifting away from visible on-system communications.
Instead, attackers may conduct negotiations through external channels such as email correspondence, direct phone contact, or dedicated dark-web portals. By moving communications outside the compromised environment, threat actors leave behind fewer artifacts that investigators can collect and reduce opportunities for automated security tools to identify the extortion phase of an attack.
To assist defenders, ThreatDown has published a collection of indicators of compromise associated with Prinz Eugen activity. These indicators can help security teams, incident responders, and researchers identify potential infections, investigate suspicious activity, and strengthen defenses against future attacks involving the ransomware.
The responsibilities placed on cybersecurity leaders are becoming increasingly difficult to manage as organizations face a growing number of cyber threats, rapid adoption of artificial intelligence technologies, and increasing demands for security oversight across the business.
A recent survey conducted by the Information Systems Security Association (ISSA) International and research firm Omdia found that 68% of cybersecurity and IT professionals believe their jobs are more difficult today than they were two years ago. More than half of respondents reported heavier workloads and greater operational complexity (55%), while 52% said the volume and intensity of cyber threats have become more overwhelming.
Security teams are being asked to protect increasingly complex digital environments while also helping organizations adopt new technologies such as generative AI. At the same time, many security leaders say they are struggling to secure sufficient support from other parts of the business.
According to Shawn Murray, former president of ISSA and a fractional Chief Information Security Officer (CISO), many security executives regularly work long hours while attempting to address security concerns that are often introduced without their involvement. In some organizations, new technologies are adopted before security teams are included in planning discussions, creating additional challenges for risk management and governance.
As a result, some experienced CISOs are leaving traditional full-time leadership positions and choosing consulting or fractional roles instead. These arrangements allow security professionals to work with multiple organizations while focusing on businesses that are willing to involve cybersecurity leaders in strategic decision-making.
While legal accountability was once considered one of the largest concerns facing CISOs, the survey suggests that anxiety around personal liability has become less prominent than in previous years. Instead, many respondents identified the security implications of artificial intelligence as one of the most significant new sources of pressure.
AI has created both opportunities and challenges for cybersecurity teams. One growing concern is the rise of "shadow AI," where employees begin using AI tools and services without notifying security teams or obtaining formal approval. Similar issues emerged during the early stages of cloud adoption, when departments could deploy new services independently without providing visibility to cybersecurity staff.
This lack of visibility can create greater security gaps. When security teams do not know which AI applications, models, or processes are being used across an organization, it becomes more difficult to identify risks, monitor suspicious activity, and respond effectively to potential incidents.
Despite these concerns, cybersecurity professionals are increasingly interested in using AI to improve their own operations. The survey found that 37% of respondents are already using AI-powered tools to address cybersecurity challenges, while another 46% plan to adopt such technologies in the future.
Among the most common use cases identified by respondents were automated cybersecurity assessments, software testing, predictive risk analysis, and threat detection. These capabilities could help security teams reduce manual workloads and process large volumes of security data more efficiently.
Alex Hutton, CISO at Atlantic Union Bank, noted that the cybersecurity environment has changed significantly in recent years. Whether organizations fully embrace advanced AI systems or not, security professionals must continuously learn about new technologies, understand emerging risks, and adapt their security strategies accordingly.
The survey also highlighted a notable shift in how organizations obtain cybersecurity leadership. The percentage of companies employing full-time CISOs declined from 76% in 2024 to 63%, while the use of fractional CISOs increased from 6% to 15% over the same period.
Industry observers believe this trend reflects growing demand for cybersecurity expertise rather than a reduction in the importance of the CISO role. Many small and mid-sized organizations face the same security, compliance, and governance challenges as larger enterprises but often lack the budget required to hire a full-time executive.
Cyber insurance requirements are also contributing to demand for experienced security leadership. Organizations are increasingly expected to demonstrate strong cybersecurity practices and effective risk management controls before obtaining coverage or meeting insurer requirements. CISOs frequently play a central role in helping businesses assess risks, improve security programs, and document compliance efforts.
According to Hutton, the rise of fractional and virtual CISOs provides organizations with access to executive-level security guidance without requiring a full-time appointment. Rather than signaling the decline of cybersecurity leadership positions, the change may represent an expansion of cybersecurity services to organizations that previously could not afford dedicated executive expertise.
As cyber threats continue to grow and AI reshapes business operations, cybersecurity leaders are expected to remain critical decision-makers. However, the role itself is changing, requiring security professionals to balance technical oversight, business strategy, regulatory expectations, and emerging technologies in an increasingly demanding environment.
The ransomware operation known as INC has grown into one of the most active cybercrime groups of 2026, with security researchers linking it to more than 830 victims since it first appeared in August 2023.
According to researchers at Acronis, the group's rise coincided with disruptions affecting major ransomware brands such as LockBit and BlackCat. As affiliates sought alternative platforms, INC appears to have benefited from that shift. More than 65% of the victims listed by the group are based in the United States, with legal firms, healthcare providers, manufacturers, construction companies, and technology organizations among the most frequently targeted sectors.
Researchers also observed major changes to the ransomware itself. INC's malware for Windows and Linux/VMware ESXi systems has been rewritten in Rust, a programming language increasingly adopted by malware developers because it supports multiple operating systems and can complicate reverse-engineering efforts.
The group's toolkit has expanded as well. Recent attacks have involved a credential-stealing utility capable of extracting authentication data from newer Veeam backup deployments that use salted DPAPI encryption. Access to backup infrastructure can give attackers valuable credentials while also making recovery efforts more difficult for victims.
Acronis noted that the sale of INC's Windows and Linux ransomware variants on underground cybercrime forums in May 2024 contributed to the appearance of related ransomware families, including Lynx and Sinobi. Researchers identified significant code similarities between the groups.
Investigators found that INC affiliates rely on several entry points to compromise networks, including spear-phishing campaigns, credentials purchased from Initial Access Brokers (IABs), and the exploitation of publicly exposed systems running vulnerable versions of Citrix NetScaler, Fortinet EMS, and SimpleHelp software.
Once inside a network, attackers harvest credentials, move between systems using legitimate administrative tools such as RDP and PsExec, and attempt to weaken security controls through a technique known as Bring Your Own Vulnerable Driver (BYOVD). Researchers observed the use of vulnerable drivers including filwfp.sys, filnk.sys, and fildds.sys. The group also deploys tools such as Cobalt Strike, AnyDesk, ScreenConnect, and TeamViewer to maintain access and control compromised environments.
Before encryption begins, stolen files are collected and transferred using Rclone, often after being packaged into password-protected archives. The ransomware then encrypts systems using multithreading and partial-encryption techniques to speed up the process. When launched against VMware ESXi environments, the malware can also attempt to shut down virtual machines.
Data from ZeroFox ranked INC as the fourth most active ransomware operation during the first quarter of 2026, recording more than 120 incidents. Researchers said the group's growth demonstrates how ransomware operators can build large-scale campaigns using widely available tools, stolen credentials, and unpatched systems rather than relying on highly specialized malware.
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