Article
Endpoint Detection and Response: The Closest Thing to a Silver Bullet to Stop Ransomware
Security Recommendations
In its recent report “Combating Ransomware,” the Ransomware Task Force says there’s no silver bullet to solving the ransomware challenge. Instead, the group touts a multi-pronged approach and provides an extensive list of recommendations to help companies better defend against this growing threat.
While I don’t disagree, for example, that coordinated global action and greater awareness to the severity of this threat are necessary, I couldn’t help but notice a glaring omission from their list: behavioral endpoint detection and response (EDR).
Why aren’t more companies using EDR solutions to combat ransomware?
For our clients, our number one recommendation to prevent or recover from a ransomware attack is to deploy endpoint protection. It’s the closest thing to a ransomware silver bullet you’re going to find — and should be a best practice.
EDR solutions are not based on malicious signatures that ransomers can easily evade. Rather, behavior-based EDR tools search for suspicious patterns of behavior that could indicate malware. And unlike antivirus, they are capable of spotting yet unknown malware, including more sophisticated threats like zero-day attacks; and they combine real-time continuous monitoring with automated analysis and response.
Cost effectiveness of EDR
EDR is not costly, especially considering the potential expense of a ransomware attack. Beyond the ransom payment itself come all the associated attack costs. As Kevin Baker detailed in his “Hidden Costs of Cybercrime” blog, companies must understand that, in the event of an attack, they will be paying for: remediation, repair, restoration of data and IT infrastructure, legal counsel, litigation defense, breach notification, business downtime, reputation damage and lost customer trust, regulatory fines, and increased insurance rates.
Many companies choose to stick with traditional antivirus solutions because they are a slightly less expensive option than EDR. But while EDR may cost more upfront, it’s much more cost-effective in the long run. And too many companies are realizing this after it’s too late, once they’ve been hacked and painfully understand they should have and need to invest more in security.
Ease of deployment and effectiveness
EDR is as quick and easy to deploy as a traditional antivirus solution. Like antivirus, EDR is agent-based, and organizations can automatically install it via a group policy or on an individual basis and, within a day, begin to reap the solution’s benefits.
When Arete’s incident response teams are called on to help victims recover from ransomware attacks — on average, 50 cases per month — this speed and ease of deployment are critical. They immediately deploy EDR technology to contain the attack and provide clients with a clean, safe environment to restore their data and operations.
On top of EDR solutions being intuitive and not requiring a high-level of security expertise, they are incredibly effective, offering functionality far beyond the basic scanning, detection, and “known” malware removal of a traditional antivirus tool. They are designed to protect all endpoints, automatically identify suspicious activity, and mitigate threats in real time. In the case of ransomware, this can mean stopping ransomware encryption, lateral movement, and data exfiltration.
At Arete, we’ve only seen threat actors successfully attack behavior-based EDR systems four times in the past five years. In two of those cases, the client had not fully deployed the EDR solution to all endpoints on the network; in the other two, the client had not protected the EDR management console with two-factor access control, which allowed the attackers to turn off the EDR system.
By comparison, antivirus solutions continue to fall a bit short on effectiveness. Because they are based on pre-populated signatures, attackers can easily evade them with simple changes to their code and sadly, almost all the ransomware victims Arete has worked with have had an antivirus solution in place that failed to detect or block the attack.
If the government can’t solve the ransomware problem, what can I do?
It’s good that the U.S. and international governments are calling for actions to end the ransomware scourge — a threat the director of the FBI has likened to the 9/11 terror attacks. Unfortunately, time is not on anyone’s side.
The daily costs of ongoing ransomware attacks to companies and their clients are too high to wait for possible government action — especially when a cost-effective, near-silver-bullet solution is at hand. If organizations, of any size, want to put ransomware attackers out of business, they should look to deploy behavior-based EDR systems today.
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Article
Ransomware Trends & Data Insights: February 2026
After a slight lull in January, Akira and Qilin returned to dominating ransomware activity in February, collectively accounting for almost half of all engagements that month. The rest of the threat landscape remained relatively diverse, with a mix of persistent threats like INC and PLAY, older groups like Cl0p and LockBit, and newer groups like BravoX and Payouts King. Given current trends, the first quarter of 2026 will likely remain relatively predictable, with the top groups from the second half of 2025 continuing to operate at fairly consistent levels month to month.
Figure 1. Activity from the top 5 threat groups in February 2026
Throughout the month of February, analysts at Arete identified several trends behind the threat actors perpetrating cybercrime activities:
In February, Arete observed Qilin actively targeting WatchGuard Firebox devices, especially those vulnerable to CVE-2025-14733, to gain initial access to victim environments. CVE-2025-14733 is a critical vulnerability in WatchGuard Fireware OS that allows a remote, unauthenticated threat actor to execute arbitrary code. In addition to upgrading WatchGuard devices to the latest Firebox OS version, which patches the bug, administrators are urged to rotate all shared secrets on affected devices that may have been compromised and may be used in future campaigns.
Reports from February suggest that threat actors are increasingly exploring AI-enabled tools and services to scale malicious activities, demonstrating how generative AI is being integrated into both espionage and financially motivated threat operations. The Google Threat Intelligence Group indicated that state-backed threat actors are leveraging Google’s Gemini AI as a force multiplier to support all stages of the cyberattack lifecycle, from reconnaissance to post-compromise operations. Separate reporting from Amazon Threat Intelligence identified a threat actor leveraging commercially available generative AI services to conduct a large-scale campaign against FortiGate firewalls, gaining access through weak or reused credentials protected only by single-factor authentication.
The Interlock ransomware group recently introduced a custom process-termination utility called “Hotta Killer,” designed to disable endpoint detection and response solutions during active intrusions. This tool exploits a zero-day vulnerability (CVE-2025-61155) in a gaming anti-cheat driver, marking a significant adaptation in the group’s operations against security tools like FortiEDR. Arete is actively monitoring this activity, which highlights the growing trend of Bring Your Own Vulnerable Driver (BYOVD) attacks, in which threat actors exploit legitimate, signed drivers to bypass and disable endpoint security controls.
Sources
Arete Internal
Article
ClickFix Campaign Delivers Custom RAT
Security researchers identified a sophisticated evolution of the ClickFix campaign that aims to compromise legitimate websites before delivering a five-stage malware chain, culminating in the deployment of MIMICRAT. MIMICRAT is a custom remote access trojan (RAT) written in the C/C++ programming language that offers various capabilities early in the attack lifecycle. The attack begins with victims visiting compromised websites, where JavaScript plugins load a fake Cloudflare verification that tricks users into executing a malicious PowerShell script, further displaying the prominence and effectiveness of ClickFix and its user interaction techniques.
Not Your Average RAT
MIMICRAT displays above-average defense evasion and sophistication, including:
A five-stage PowerShell sequence beginning with Event Tracing for Windows and Anti-Malware Scan Interface bypasses, which are commonly used in red teaming for evading detection by EDR and AV toolsets.
The malware later uses a lightweight scripting language that is scripted into memory, allowing malicious actions without files that could easily be detected by an EDR tool.
MIMICRAT uses malleable Command and Control profiles, allowing for a constantly changing communication infrastructure.
The campaign uses legitimate compromised infrastructure, rather than attacker-owned tools, and is prepped to use 17 different languages, which increases global reach and defense evasion.
Analyst Comments
The ClickFix social engineering technique remains an effective means for threat actors to obtain compromised credentials and initial access to victim environments, enabling them to deploy first-stage malware. Coupled with the sophisticated MIMICRAT RAT, the effectiveness of this campaign could increase. Arete will continue monitoring for changes to the ClickFix techniques, the deployment of MIMICRAT in other campaigns, and other pertinent information relating to the ongoing campaign.
Sources
MIMICRAT: ClickFix Campaign Delivers Custom RAT via Compromised Legitimate Websites
Article
Threat Actors Leveraging Gemini AI for All Attack Stages
State-backed threat actors are leveraging Google’s Gemini AI as a force multiplier to support all stages of the cyberattack lifecycle, from reconnaissance to post-compromise operations. According to the Google Threat Intelligence Group (GTIG), threat actors linked to the People’s Republic of China (PRC), Iran, North Korea, and other unattributed groups have misused Gemini to accelerate target profiling, synthesize open-source intelligence, identify official email addresses, map organizational structures, generate tailored phishing lures, translate content, conduct vulnerability testing, support coding tasks, and troubleshoot malware development. Cybercriminals are increasingly exploring AI-enabled tools and services to scale malicious activities, including social engineering campaigns such as ClickFix, demonstrating how generative AI is being integrated into both espionage and financially motivated threat operations.
What’s Notable and Unique
Threat actors are leveraging Gemini beyond basic reconnaissance, using it to generate polished, culturally nuanced phishing lures and sustain convincing multi-turn social engineering conversations that minimize traditional red flags.
In addition, threat actors rely on Gemini for vulnerability research, malware debugging, code generation, command-and-control development, and technical troubleshooting, with PRC groups emphasizing automation and vulnerability analysis, Iranian actors focusing on social engineering and malware development, and North Korean actors prioritizing high-fidelity target profiling.
Beyond direct operational support, adversaries have abused public generative AI platforms to host deceptive ClickFix instructions, tricking users into pasting malicious commands that deliver macOS variants of ATOMIC Stealer.
AI is also being integrated directly into malware development workflows, as seen with CoinBait’s AI-assisted phishing kit capabilities and HonestCue’s use of the Gemini API to dynamically generate and execute in-memory C# payloads.
Underground forums show strong demand for AI-powered offensive tools, with offerings like Xanthorox falsely marketed as custom AI but actually built on third-party commercial models integrated through open-source frameworks such as Crush, Hexstrike AI, LibreChat-AI, and Open WebUI, including Gemini.
Analyst Comments
The increasing misuse of generative AI platforms like Gemini highlights a rapidly evolving threat landscape in which state-backed and financially motivated actors leverage AI as a force multiplier for reconnaissance, phishing, malware development, and post-compromise operations. At the same time, large-scale model extraction attempts and API abuse demonstrate emerging risks to AI service integrity, intellectual property, and the broader AI-as-a-Service ecosystem. While these developments underscore the scalability and sophistication of AI-enabled threats, continued enforcement actions, strengthened safeguards, and proactive security testing by providers reflect ongoing efforts to mitigate abuse and adapt defenses in response to increasingly AI-driven adversaries.
Sources
GTIG AI Threat Tracker: Distillation, Experimentation, and (Continued) Integration of AI for Adversarial Use
Article
2025 VMware ESXi Vulnerability Exploited by Ransomware Groups
Ransomware groups are actively exploiting CVE‑2025‑22225, a VMware ESXi arbitrary write vulnerability that allows attackers to escape the VMX sandbox and gain kernel‑level access to the hypervisor. Although VMware (Broadcom) patched this flaw in March 2025, threat actors had already exploited it in the wild, and CISA recently confirmed that threat actors are exploiting CVE‑2025‑22225 in active campaigns.
What’s Notable and Unique
Chinese‑speaking threat actors abused this vulnerability at least a year before disclosure, via a compromised SonicWall VPN chain.
Threat researchers have observed sophisticated exploit toolkits, possibly developed well before public disclosure, that chain this bug with others to achieve full VM escape. Evidence points to targeted activity, including exploitation via compromised VPN appliances and automated orchestrators.
Attackers with VMX level privileges can trigger a kernel write, break out of the sandbox, and compromise the ESXi host. Intrusions observed in December 2025 showed lateral movement, domain admin abuse, firewall rule manipulation, and staging of data for exfiltration.
CISA has now added CVE-2025-22225 to its Known Exploited Vulnerabilities (KEV) catalog, underscoring ongoing use by ransomware attackers.
Analyst Comments
Compromise of ESXi hypervisors significantly amplifies operational impact, allowing access to and potential encryption of dozens of VMs simultaneously. Organizations running ESXi 7.x and 8.x remain at high risk if patches and mitigations have not been applied. Therefore, clients are recommended to apply VMware patches from VMSA‑2025‑0004 across all ESXi, Workstation, and Fusion deployments. Enterprises are advised to assess their setups in order to reduce risk, as protecting publicly accessible management interfaces is a fundamental security best practice.
Sources
CVE-2025-22225 in VMware ESXi now used in active ransomware attacks
The Great VM Escape: ESXi Exploitation in the Wild
VMSA-205-004: VMware ESXi, Workstation, and Fusion updates address multiple vulnerabilities (CVE-205-22224, CVE-2025-22225, CVE-2025-22226)