Article
The Road Back: Recovery from a Malware Attack in the Long Term
Arete Analysis
Cybersecurity 101
Arete Incident Response is currently answering the call of duty for about 60 companies per month who have experienced malware intrusions. These are mostly ransomware or business email compromise attacks. Arete’s primary goal is to restore what was broken and get the client back into business. However, another important goal is to harden the client’s IT environment against future attacks.
The steps taken by Arete commonly involve the following:
Implementing a more secure login process, such as two factor authentication—especially for remote access
Installing endpoint protection agents, which some call “Next Gen AV”, but are far more than just antivirus software
Minimizing the attack service by disabling unneeded services and protocols; and
Changing passwords, particularly on administrative accounts.
During the initial stages of the response process, the Arete team is completely focused on remediating the malware and getting the client’s critical systems back online. But what does this experience mean for the future of the company? Usually, the business owner has some regret about not having taken sufficient security precautions before the incident, and the question always arises: “How do we keep this from happening again?”
One critical piece has already been implemented – endpoint protection. Comprehensive coverage of the network boundaries increases the chances that intrusions will be detected. However, cyber-extortion/ransomware and the malware that enables it can evolve rapidly and
require a continuously trained staff to thwart. Acquiring, retaining, and training adequate staff is beyond the capability of many businesses. A cybersecurity firm offering vCISO (virtual chief security officer) services can provide the needed expertise to ensure that the business develops a formal information security program that addresses current risk, as well as prepares for the next wave of attacks.
Preventing the recurrence of a breach involves more than technology and requires a more comprehensive approach to security. Information security is not just a technical problem–it is a business problem. It should be approached in the same methodical fashion by which other business problems are managed. Just as the company has a “quality culture” for products, it must be understood that security is just another aspect of product and service quality. Quality is achieved through deliberate and continuous actions. The development of policies, standards of behavior, and contingency protocols for security should run parallel to the critical business processes that generate revenue. A successful security program requires some investment, but in the long run pays off in safeguarding the business’ data, intellectual property, consumer information, business processes and most importantly, its reputation.
A comprehensive treatment of a full security program is beyond the scope of this article. Nevertheless, significant components include:
IT policy that clearly establishes expectations that management has regarding the protection and handling of company/customer data, company technology and resources.
IT infrastructure review for assessing the current state of company technology and means of access to that technology, with a roadmap of continuous security improvement.
Data security and privacy reviews that map the movement and protection of sensitive data as that data traverses the critical business activities and processes.
Special attention should be paid to understanding what is most important to continue generating revenue, with contingency planning for disaster recovery and business resilience for each critical process. The people, processes and technology that actually make the business what it is should be well understood, documented, and have redundant resources for ensuring continuous operations, even during a cyber-attack.
Spending on improving the security posture of a business can be a hard pill to swallow, particularly after expenses from a breach come in, but there will never be a better moment to tackle it. Security events can be a focal point for employee awareness, and the need to heighten that awareness will never make more sense than in the days following the event. Building a culture of security and framing the effort required as just another part of the business day is a relatively low-cost way to improve. Other investments in maturing processes and technology will probably be required to ensure a secure future for the business. The best way to spend on security could be to acquire the services of those who have built programs before, at least until there is a functioning security program that can stand on its own two feet.
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Article
FortiGate Exploits Enable Network Breaches and Credential Theft
A recent security report indicates that threat actors are actively exploiting FortiGate Next-Generation Firewall (NGFW) appliances as initial access vectors to compromise enterprise networks. The activity leverages recently disclosed vulnerabilities or weak credentials to gain unauthorized access and extract configuration files, which often contain sensitive information, including service account credentials and detailed network topology data.
Analysis of these incidents shows significant variation in attacker dwell time, ranging from immediate lateral movement to delays of up to two months post-compromise. Since these appliances often integrate with authentication systems such as Active Directory and Lightweight Directory Access Protocol (LDAP), their compromise can grant attackers extensive access, substantially increasing the risk of widespread network intrusion and data exposure.
What’s Notable and Unique
The activity involves the exploitation of recently disclosed security vulnerabilities, including CVE-2025-59718, CVE-2025-59719, and CVE-2026-24858, or weak credentials, allowing attackers to gain administrative access, extract configuration files, and obtain service account credentials and network topology information.
In one observed incident, attackers created a FortiGate admin account with unrestricted firewall rules and maintained access over time, consistent with initial access broker activity. After a couple of months, threat actors extracted and decrypted LDAP credentials to compromise Active Directory.
In another case, attackers moved from FortiGate access to deploying remote access tools, including Pulseway and MeshAgent, while also utilizing cloud infrastructure such as Google Cloud Storage and Amazon Web Services (AWS).
Analyst Comments
Arete has identified multiple instances of Fortinet device exploitation for initial access, involving various threat actors, with the Qilin ransomware group notably leveraging Fortinet device exploits. Given their integration with systems like Active Directory, NGFW appliances remain high-value targets for both state-aligned and financially motivated actors. In parallel, Arete has observed recent dark web activity involving leaked FortiGate VPN access, further highlighting the expanding risk landscape. This aligns with the recent reporting from Amazon Threat Intelligence, which identified large-scale compromises of FortiGate devices driven by exposed management ports and weak authentication, rather than vulnerability exploitation. Overall, these developments underscore the increasing focus on network edge devices as entry points, reinforcing the need for organizations to strengthen authentication, restrict external exposure, and address fundamental security gaps to mitigate the risk of widespread compromise.
Sources
FortiGate Edge Intrusions | Stolen Service Accounts Lead to Rogue Workstations and Deep AD Compromise
Article
Vulnerability Discovered in Anthropic’s Claude Code
Security researchers discovered two critical vulnerabilities in Anthropic's agentic AI coding tool, Claude Code. The vulnerabilities, tracked as CVE-2025-59536 and CVE-2026-21852, allowed attackers to achieve remote code execution and to compromise a victim's API credentials. The vulnerabilities exploit maliciously crafted repository configurations to circumvent control mechanisms. It should be noted that Anthropic worked closely with the security researchers throughout the process, and the bugs were patched before the research was published.
What’s Notable and Unique
The configuration files .claude/settings.json and .mcp.json were repurposed to execute malicious commands. Because the configurations could be applied immediately upon starting Claude Code, the commands ran before the user could deny permissions via a dialogue prompt, or they bypassed the authentication prompt altogether.
.claude/settings.json also defines the endpoint for all Claude Code API communications. By replacing the default localhost URL with a URL they own, an attacker could redirect traffic to infrastructure they control. Critically, the authentication traffic generated upon starting Claude Code included the user's full Anthropic API key in plain text and was sent before the user could interact with the trust dialogue.
Restrictive permissions on sensitive files could be bypassed by simply prompting Claude Code to create a copy of the file's contents, which did not inherit the original file's permissions. A threat actor using a stolen API key could gain complete read and write access to all files within a workspace.
Analyst Comments
The vulnerabilities and attack paths detailed in the research illustrate the double-edged nature of AI tools. The speed, scale, and convenience characteristics that make AI tools attractive to developer teams also benefit threat actors who use them for nefarious purposes. Defenders should expect adversaries to continue seeking ways to exploit configurations and orchestration logic to increase the impact of their attacks. Organizations planning to implement AI development tools should prioritize AI supply-chain hygiene and CI/CD hardening practices.
Sources
Caught in the Hook: RCE and API Token Exfiltration Through Claude Code Project Files | CVE-2025-59536 | CVE-2026-21852
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