Article
Conti Ransomware is the New Ryuk?
Arete Analysis

Summary
Arete’s Threat Intelligence team observed that Conti ransomware could be a rebrand of Ryuk ransomware, as both variants use similar tactics to deploy ransomware executables.
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Background
Based on analysis of Conti ransomware, which was originally spotted in the wild in February of this year, the Arete Threat Intelligence team believes that this variant is being operated by the same group that conducted Ryuk ransomware attacks in the past. Digital forensics analysis of systems impacted by Conti ransomware revealed that it is generally being deployed by the attackers using the TrickBot banking trojan. Since early 2019, Ryuk ransomware operators exclusively used TrickBot trojan in their operations. In the 1st quarter of 2020, the number of Ryuk ransomware attacks significantly declined while the number of new Conti matters started to rise, which is a secondary indicator of a connection between both variants.
Conti Overview
Conti is a sophisticated ransomware variant that emerged in February 2020. Unlike most of its’ peers, Conti ransomware encrypts files on victims’ machines significantly faster by running 32 concurrent threads and utilizing all computing power that impacted systems have available. As a result of that, devices with multi-core CPUs get encrypted quicker. Conti has the capability to encrypt local hard drives, network shares and other devices on the local network. To encrypt the data, Conti uses the AES-256 encryption key, which is bundled with the RAS-4096 public encryption key (Note: this key is unique for each victim). Since the encryption key is unique for each victim, Conti operators cannot provide a decryption tool, which would work only on specific devices. The Conti decryption tool works on all encrypted systems within a victim’s networks.
Prior to the start of the encryption, Conti leverages Windows Restart Manager to disable security, backups and other applications that may keep files locked on the impacted systems. Then it deletes Shadow Volume copies to make it impossible to use built-in Windows volume backups to restore data after the encryption.
Once encryption completes, the .CONTI extension is added to all encrypted files and the ransom note, CONTI_README.txt, is placed in each folder. Each ransom note contains 2 email addresses to get in touch with the attackers, which are unique for each victim. This method is consistent with what Ryuk operators used in their attacks. Conti operators use a unique set of emails to identify each victim, so it does not matter if a victim responds from a corporate account or from a public email account – attackers still will know which victim they are communicating with. Just like Ryuk, Conti conducts research into information about their victims and sets ransom demands based on what they believe the victim can afford to pay.
Conti Ransom Note

Figure 1 - % of Data Exfiltration in Ryuk matters
It was uncommon for Ryuk to exfiltrate data from victims’ systems. Based on Arete analysis of previous matters, we only observed data exfiltration in 7% of cases. Unlike Ryuk, it appears that Conti ransomware operators decided to join the bandwagon of other 20+ variants that steal data from victims’ environments prior to the encryption. Conti also created a web site where they publish lists of their victims in attempt to improve their chances of getting paid. In the last few weeks, Conti stepped up their extortion attempts and, in some cases, called the owner/managers of companies directly, to inform them that they have been compromised and threaten them to release the stolen data if they don’t pay.
Security Recommendations
Below are a few recommendations that will help to protect your organization from Conti ransomware attacks:
Implement a sophisticated Endpoint Detection & Response (EDR) solution that will rely on behavior analysis, instead of just malware signatures, and have tamper-proof capabilities.
Keep your systems updated and disable SMBv1, to protect against Windows EternalBlue vulnerability, which is actively being used by the TrickBot banking trojan to propagate within a victims’ environment.
Block outbound traffic on your firewall for ports 447, 449 & 8082 (Note: along with 443 those ports are commonly used by TrickBot) and implement geo-blocking for foreign countries that you don’t have any employees in and don’t do business with.
Continuously educate your users on how to identify suspicious phishing emails and attachments.
Implement an off-site backup solution and test it regularly

Figure 2 - Screenshot of the Conti exfil site
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Article
Top 9 Security Controls for SMBs
In today’s complex cyber threat landscape, small and medium-sized businesses (SMBs) should implement a layered, multi-pronged approach to security. Here are some proven, effective controls to consider:
1. Implement MFA for All Users
Multi-factor authentication (MFA) is an effective and accessible way to protect sensitive data, comply with regulatory standards, and prevent unauthorized access to critical systems. By ensuring that users not only use a password but also a secure token, an organization can significantly reduce phishing attempts, credential stuffing attacks, and ransomware incidents. MFA should be enabled for email, VPN, and critical system access.
2. Update Patch Management Programs
A modern patching program should include policies and mechanisms to manage software updates in a timely manner. Patching efforts should address not just operating system updates, but also commonly utilized software within the environment. An active patching plan aims to reduce the mean time to patch and provide metrics on existing patch efforts. In the event of a high-severity vulnerability, a mature patching program should also be able to identify the risks and exposure for a given set of systems based on the average time to patch. This helps stakeholders make informed decisions when a new exploit is released.
3. Leverage a Properly Managed Endpoint Detection and Response (EDR) Tool
With real-time threat detection and advanced visibility, endpoint detection and response (EDR) solutions can enhance an organization’s ability to detect and investigate potential malicious activity, including ransomware, lateral movement, fileless attacks, and more. Effective management of EDR should include proper configuration, regular agent updates, and established procedures for responding to alerts.
4. Enhance EDR with Frontline Incident Intelligence
While EDR solutions are an important component of a security program, threat actors are continually adapting their techniques to evade detection, and as a result, standard detection methods may not always identify emerging threats or novel attack behaviors. To strengthen protection, organizations can supplement EDR tools with custom detection rules informed by incident response data. These rules can help identify indicators of compromise observed during cyber incidents, providing an additional layer of visibility beyond traditional detections.
Arete Bloktd℠ illustrates this approach by transforming threat intelligence and malware analysis into curated detection rules for EDR tools. Applying frontline intelligence to security tools can result in earlier detection, less investigative burden, and a more confident response.
5. Create and Continuously Test an Incident Response (IR) Plan
An incident response plan can help an organization effectively identify, respond to, and recover from a cybersecurity incident while minimizing disruption and downtime. An IR plan defines clear roles, escalation paths, communication strategies, and decision frameworks for both internal and external teams. To be effective, these plans should be regularly tested with post-incident reviews or tabletop exercises involving key stakeholders.
6. Maintain Encrypted and Tested Data Backups
In the case of a cyberattack, backups can help organizations maintain business continuity, support ransom negotiations with threat actors, and contribute to a timely and successful recovery. Encrypting backups makes it more difficult for threat actors to access or alter them, and regular testing ensures they remain accessible during a security incident.
7. Conduct Employee Security Awareness Training
Human error is a leading cause of cybersecurity incidents, and an organization’s employees are its first line of defense against cyber threats. Security awareness training reinforces the importance of data confidentiality, supports regulatory compliance, and helps employees recognize and understand red flags such as suspicious emails, malicious links, and social engineering attempts.
8. Assess and Address Existing Risk and Vulnerabilities
To maintain a proactive approach to risk management and improve resilience, organizations should regularly assess existing vulnerabilities through expert-led Vulnerability Assessments, Penetration Testing, and Threat Hunting Assessments. These exercises can help identify security gaps, support regulatory compliance, and prevent potential incidents. During remediation, prioritize high-impact vulnerabilities and make a plan for periodic assessments.
9. Apply Least-Privilege Access Controls
Employees should have access only to the systems, applications, and data necessary to perform their jobs. By removing unnecessary administrative privileges and regularly reviewing user permissions, organizations can reduce the risk of unauthorized access and limit the damage caused by compromised accounts or insider threats.
Organizations should regularly review their cybersecurity programs, stay informed about emerging threats, and evaluate whether their security controls are adapting to the evolving threat landscape.
Article
Ransomware Trends & Data Insights: August 2026
Although INC Ransom was the most active ransomware threat group observed in August 2026, overall activity remained relatively distributed across the threat landscape, with approximately 30 unique ransomware and extortion groups, including both established and newly emerged actors, observed during the month. Alongside INC Ransom, Storm, DragonForce, Qilin, and The Gentlemen were among the top five most active threat groups, underscoring the continued diversity and competitiveness of the ransomware ecosystem.

Figure 1. Activity from the top 5 threat groups in August 2026
Throughout the month, analysts at Arete identified several trends behind the threat actors perpetrating cybercrime activities:
August 2026 was a significant month for the emergence of new threat actors, with Arete identifying several previously untracked ransomware groups, including Storm, Dark Project, DireWolf, Morpheus, Orova, Spirals, Wallstreet Team, and Zawoo Team. This trend underscores the ongoing evolution of the threat landscape and the low barriers to entry for new cybercriminal operations.
Arete observed a continued use of AI-enabled capabilities across the ransomware ecosystem during August. Similar to Fulcrumsec and Setra, the newly emerged Zawoo Team appears to leverage AI-assisted analysis of stolen data, publishing highly structured and detailed victim assessments on its data leak site (DLS). Additionally, both the Aurora and Storm ransomware groups have been observed utilizing AI-driven or AI-assisted chat representatives during victim communications. These developments suggest that threat actors are increasingly incorporating AI to enhance data analysis, automate victim engagement, and improve the effectiveness and scalability of extortion operations.
In August, Arete also observed that despite sustained law enforcement disruption efforts, LockBit continues to demonstrate operational resilience, likely through the expansion of its affiliate ecosystem and the evolution of its tactics. Recent activity indicates an increased reliance on data theft and exfiltration-only operations, with observed victimology suggesting a notable focus on organizations within the financial sector.
Sources
Arete Internal
Report
Arete's H1 2026 Crimeware Report
Explore intelligence and operational data from the frontlines of ransomware and extortion response as we detail the most significant trends and developments in the cyber threat landscape in the first half (H1) of 2026.
Article
WinRAR Path-Traversal Vulnerability Exploited in Ransomware Attacks
CISA has warned that CVE-2025-8088, a path-traversal vulnerability in WinRAR, is being exploited in ransomware attacks. The vulnerability allows attackers to use specially crafted archive files to place malicious executables in locations such as the Windows Startup folder, enabling code execution when the system restarts. WinRAR addressed this vulnerability in version 7.13, but exploitation has continued due to challenges in updating the software. CISA's updated KEV entry now specifically identifies the vulnerability as being used in ransomware attacks.
What’s Notable and Unique
The vulnerability was initially exploited as a zero-day by the Russia-linked RomCom group, enabling malware execution at user logon and supporting credential theft, cyberespionage, and ransomware-related activities.
CVE-2025-8088 continues to be actively exploited by both government-backed and financially motivated threat actors. Observed campaigns have been attributed to Russian- and Chinese-linked groups targeting several organizations.
Phishing campaigns leveraging weaponized RAR attachments exploited CVE-2025-8088 to silently place malicious payloads in autorun locations using directory traversal and Alternate Data Streams (ADS).
The widespread exploitation of CVE-2025-8088 highlights strong demand for effective WinRAR exploits, with multiple underground vendors previously supplying exploit capabilities to a diverse range of threat actors. One such vendor, zeroplayer, advertised a WinRAR exploit in July 2025.
Analyst Comments
Organizations should immediately upgrade WinRAR to version 7.13 or later and conduct an enterprise-wide inventory to identify unmanaged installations. Given that WinRAR lacks automatic updates, Group Policy support, and integration with common enterprise patch management platforms, manual verification and remediation may be required to ensure all vulnerable instances are addressed. Security teams should also enhance defenses against archive-based phishing attacks by blocking or scrutinizing unsolicited compressed files, monitoring for suspicious file creation in Windows Startup directories, and detecting abuse of ADS. With CISA now linking CVE-2025-8088 to ransomware activity, organizations should treat remediation as a high priority and actively monitor for indicators of WinRAR-based exploitation across their environments.
Sources
CISA Adds Three Known Exploited Vulnerabilities to Catalog
WinRAR vulnerability being exploited in ransomware attacks, CISA warns



