Article
Managed File Transfer Exploits: Here to Stay?
Arete Analysis
Cybersecurity Trends
Threat Actors

Cybercriminals are actively exploiting recently disclosed vulnerabilities in two prominent Managed File Transfer (MFT) products. Initially discovered by cybersecurity researchers, CVE-2025-11371 is an unauthenticated Local File Inclusion vulnerability in Gladinet’s MFT product, CentreStack. This vulnerability ultimately enables an exploit chain allowing remote code execution (RCE) that was patched by Gladinet earlier this year (CVE-2025-30406).
Meanwhile, Fortra confirmed the targeting of a vulnerability, CVE-2025-10035, in its GoAnywhere MFT product. Although the extent of this latest campaign is unknown, researchers have observed ongoing exploitation of the vulnerability by a threat group known for deploying Medusa ransomware. The vulnerability also results in RCE due to improper deserialization.
Both vendors have patched these vulnerabilities in their product’s latest version.
What’s Notable and Unique
The recent attacks against Gladinet CentreStack are the second concerted effort this year to exploit vulnerabilities in this product. This speaks to threat actors’ perceived value of the source and the associated data. Given the access to sensitive data and broad reach within the network that generally accompany MFT systems, it’s easy to see why cybercriminals continue to return to this product.
Although patches for both CentreStack and GoAnywhere MFT have been released, Arete recommends that organizations continue to proactively hunt for any suspicious activity involving these products. In recent years, cybercriminals have heavily targeted and leveraged MFT software in their operations. Arete does not foresee any near-term deviation in this trend.
Analyst Comments
The activity described in this article is far from novel and in no way isolated. This summer, security researchers warned of notable surges in scanning activity targeting the well-known (and previously exploited) MFT software, MOVEit. CrushFTP and Cleo’s LexiCom, VLTransfer, and Harmony products have also received attention from threat actors this year. Although MFT products are powerful tools for a business, they also present an enticing target for cybercriminals and should be evaluated and deployed with care and closely monitored. Arete has responded to several incidents in which MFT software was utilized by the threat actor. Cybercriminals view these platforms not only as a way to access sensitive data, but also as an ideal vector for initial entry into a network, making continued exploitation likely for the foreseeable future.
Sources
Active Exploitation of Gladinet CentreStack and Triofox Local File Inclusion Flaw (CVE-2025-11371)
Investigating active exploitation of CVE-2025-10035 GoAnywhere Managed File Transfer vulnerability
Fortra cops to exploitation of GoAnywhere file-transfer service defect
Deserialization Vulnerability in GoAnywhere MFT’s License Servlet
Threat Advisory: Oh No Cleo! Cleo Software Actively Being Exploited in the Wild
MOVEit Transfer Faces Increased Threats as Scanning Surges and CVE Flaws Are Targeted
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Digital Forensics Meets the Courtroom: Insights on Expert Witness and Cyber-Related Litigation
In this episode of Bytes of Insight, host Vinny Sakore and special guest Dr. Bruce Hartley, Managing Director and Co-Founder of Advisory Services at Arete, discuss the evolving role of digital forensics and expert witness work in cybersecurity litigation. Tune in for firsthand insights on how Arete conducts post-breach investigations, what it takes to undergo cross-examination on the stand, and how emerging threats like AI-driven social engineering and third-party breaches are reshaping the advisory landscape.
Article
Helix Extortion Group Debuts in SharePoint Data Theft Attacks
A newly identified data-extortion group, Helix, is reportedly conducting targeted campaigns by exploiting identity-based attack techniques to gain access to Microsoft 365 environments and exfiltrate data from SharePoint Online. The group leverages voice phishing (vishing), device code phishing, and multi-factor authentication (MFA) abuse to compromise user accounts and establish unauthorized access.
Helix threat actors reportedly initiate intrusions through vishing campaigns, impersonating trusted individuals—often the target's manager—and leveraging caller ID spoofing to enhance credibility.
The actors then attempt to persuade victims to complete device code phishing workflows, enabling unauthorized access to corporate accounts and Microsoft 365 resources.
Following successful authentication, the actors conduct reconnaissance and enumeration of SharePoint environments before identifying and exfiltrating sensitive data for extortion purposes.
Helix's variable dwell times suggest a flexible, target-specific operational approach, enabling the group to adapt its intrusion timeline to victim environments to maximize data theft and extortion opportunities while minimizing the likelihood of detection. Helix's operations also appear to be focused on large-scale data theft and extortion, with an emphasis on automated SharePoint data exfiltration following successful credential or session compromise.
Overlaps with Other Extortion Groups
Researchers assess that Helix likely emerged from or has operational overlap with the ShinyHunters and BlackFile/Redact cybercriminal ecosystems. ShinyHunters historically focuses on compromising websites, developer repositories, and exposed credentials or API keys to gain access to corporate cloud environments, monetizing stolen victim data on the dark web. BlackFile utilizes identity-centric and social engineering–driven methods of intrusion, relying less on traditional malware and instead leveraging credential theft, privilege escalation, rapid data exfiltration, and coercive tactics such as swatting to maximize extortion pressure. In May 2026, BlackFile announced that it would be rebranding as “Redact” (which may have later rebranded again to “Pink”), yet despite the rebrands, threat actors operating within these groups continued to exhibit similar operational models, victimology, and extortion methodologies.
Analyst Comments
Collectively, the similarities between the groups suggest the possibility of a shared criminal ecosystem, affiliate network, or loosely connected threat cluster rather than entirely independent operations. The emergence of Helix further reflects the broader trend of extortion groups rebranding or fragmenting while retaining proven attack techniques and operational infrastructure to support their criminal activities. Despite suspicion of these groups’ connectivity, the exact nature of the relationship remains unconfirmed. As Helix focuses on identity-based attack techniques to gain access to Microsoft 365 environments, Arete recommends that organizations remain vigilant in using MFA, enforcing strong identity security controls, continuously monitoring authentication activity, and enhancing user awareness of social engineering tactics.
Sources
Helix, a New Name in the Data Extortion Ecosystem?
BlackFile actively extorting data-theft victims in retail and hospitality sector
"Pink" Data Extortion Group Hunting With Evasive Phishing Kits
Article
FortiBleed Campaign Linked to INC and Lynx Ransomware Operations
Researchers have linked the FortiBleed credential-harvesting campaign to the INC and Lynx ransomware-as-a-service (RaaS) operations, establishing a direct connection between large-scale FortiGate credential theft and subsequent ransomware deployment. The attribution is based on a variety of factors, including an operator observed managing negotiation panels for both ransomware groups, notable overlap between FortiBleed victim data and subsequent ransomware targets, and internal infrastructure exposing attack workflows. The campaign is estimated to have targeted more than 430,000 internet-facing FortiGate devices, resulting in administrative access to hundreds of organizations.
What’s Notable and Unique
Researchers identified a shared operator actively managing negotiation panels for both the INC and Lynx ransomware groups, providing rare operational evidence linking the two RaaS operations beyond infrastructure or malware similarities.
Analysis of the exposed infrastructure revealed a structured ransomware operation with dedicated roles for access acquisition, victim management, negotiations, and technical support, reflecting an organized ransomware-as-a-service (RaaS) model rather than an ad hoc criminal group.
The operation reportedly integrates artificial intelligence into multiple stages of the attack lifecycle, including vulnerability research, penetration testing, attack automation, and ransomware development, demonstrating the increasing adoption of AI to enhance offensive capabilities.
Mitigations
Organizations should assume that exposed or previously compromised FortiGate credentials may be leveraged for ransomware deployment and immediately reset administrative and VPN credentials while enforcing multi-factor authentication (MFA) for all privileged access. Security teams should ensure that FortiGate appliances are fully patched, restrict management interfaces to trusted networks, and audit administrative accounts and firewall configurations for unauthorized changes. Organizations should also monitor for anomalous authentication activity, hunt for published indicators of compromise (IOCs), and review VPN and firewall logs for signs of unauthorized access. Maintaining centralized logging and a well-practiced incident response process can help detect and contain attacks before they progress to lateral movement or ransomware deployment.
Analyst Comments
The attribution of FortiBleed to the INC and Lynx ransomware operations reinforces the growing convergence between credential-harvesting campaigns and ransomware deployment, highlighting the role of initial access operations in modern RaaS ecosystems. The relationship between INC and Lynx also aligns with Arete's previous research, which identified a shared malware lineage. INC Ransom, first observed in 2023, was later leaked or sold, enabling code reuse by other threat actors. Lynx, which emerged in 2024, is widely regarded as an evolution of the INC codebase. Sinobi ransomware, identified in 2025, shares near-identical binaries and infrastructure, and approximately 99% code similarity with Lynx. Further details on the code correlation between INC, Lynx, and Sinobi are available in Arete's 2025 Annual Report.
Sources
Is FortiBleed Linked to INC and Lynx Ransomware?
FortiBleed credential-theft campaign linked to Lynx ransomware
FortiBleed Unmasked: A Joint Operation by Lynx and INC Ransomware Groups
FortiBleed Credential Theft Campaign Attributed to INC and Lynx Ransomware Groups
Article
Ransomware Trends & Data Insights: June 2026
Although Akira was once again the most active ransomware threat in June, activity remained relatively distributed among multiple threat groups, with 17 unique threat groups observed throughout the month. Along with Akira, Qilin and INC Ransom remained active and were among the top five most active threat groups observed in June. Several new threat actors also emerged during the month, including KryBit, Settra, and Icarus.

Figure 1. Activity from the top 5 threat groups in June 2026
Throughout the month, analysts at Arete identified several trends behind the threat actors perpetrating cybercrime activities:
In June, a threat actor calling themselves Icarus compromised and exfiltrated data from customers of the market intelligence platform Klue. Klue later confirmed the security incident, which involved attackers stealing OAuth tokens used to connect to customers' Salesforce environments, and reported that the threat actor was deleting the data stolen from affected Klue customers. In an odd twist, reports emerged of a second threat actor claiming to have compromised Icarus's infrastructure and attempting to re-extort Klue's customers. Regardless, the Klue breach highlights the growing threat of software-as-a-service (SaaS) supply chain compromises, particularly those exploiting OAuth tokens and trusted integrations to bypass traditional security controls.
In mid-June, security researchers identified a large-scale credential-harvesting and valid account abuse campaign dubbed “FortiBleed” that systematically targets internet-facing Fortinet FortiGate firewalls and SSL-VPN gateways, relying heavily on automated password spraying and configuration exfiltration rather than vulnerability exploitation. The scale of exposure and attack activity has been significant and globally distributed, with attackers collecting the login credentials of over 86,000 FortiGate devices across 194 countries. There is no singular ‘fix’ to mitigate the database exposure, and it is important that organizations work with their security teams, incident response providers, and other stakeholders to review environments holistically and monitor for signs of potentially unauthorized activity.
Multiple threat groups continue to leverage vulnerable drivers to bypass endpoint detection and response (EDR) solutions in a technique known as Bring Your Own Vulnerable Driver (BYOVD). Arete has observed Akira and DragonForce using the technique in multiple engagements, and The Gentlemen ransomware-as-a-service (RaaS) has also been observed using what researchers are calling "GentleKiller", a framework consisting of multiple variants that leverage vulnerable drivers and EDR-disabling utilities to target a wide range of endpoint security products.
Sources
Arete Internal



