“Whaling” has taken on a new meaning with a highly targeted phishing campaign active from November 2025 through March 2026, aimed exclusively at senior executives from more than 20 industries. The campaign, dubbed VENOM, is a phishing-as-a-service (PhaaS) platform that combines advanced evasion capabilities with immediate persistence of targeted executives. The initial phish impersonates an internal SharePoint document notification and uses embedded QR codes to convince victims to shift to unmanaged mobile devices to bypass corporate security controls. VENOM aims to establish persistence immediately by either registering a new MFA device or retaining long-lived refresh tokens, allowing threat actors to maintain access even after password resets or other base-level remediation efforts. 

What’s Notable and Unique

•  This campaign is unique in its targeted nature of the PhaaS platform rather than broad, sweeping attempts. The threat actors behind VENOM create convincing phishing emails that impersonate SharePoint activity using the victim’s own domain, company name, and even fabricated email threads. These convincing social engineering tactics, combined with the specific targeting of executives, make this an effective capability for cybercriminals.

•  VENOM operates as a closed-access system, with full adversarial support, but has no public visibility on the dark web or from security researchers. The service likely operates on an invite-only basis, unlike most PhaaS platforms, which typically seek to have as many paying customers as possible. This, among other items such as the sophisticated evasion techniques, indicates a higher degree of sophistication than most other PhaaS offerings.

• Either through MFA enrollment or Microsoft Device Code abuse, the threat actor forces the victim to aid them in establishing persistence early in the attack lifecycle. These tactics result in either valid tokens or an additional MFA login method controlled by the threat actor, meaning typical password resets alone are not effective against this technique. Administrators would be required to explicitly revoke sessions and token grants to mitigate the threat actors’ persistence.

Analyst Comments

Oftentimes, MFA is viewed as a one-stop shop to cybersecurity, but tactics such as this show how threat actors can bypass MFA, or worse, use it to establish persistence. Ultimately, this campaign highlights how modern attacks increasingly abuse legitimate authentication workflows rather than attempting to defeat them outright. Defenses that rely solely on MFA without other security posturing, such as continuous session monitoring, token revocation, and identity logging, can leave organizations vulnerable. As attackers shift toward token theft and device trust abuse, incident response and identity security strategies must evolve accordingly.

Sources

• Meet VENOM: The PhaaS Platform That Neutralizes MFA

Multiple ransomware operations have recently been observed leveraging the Bring Your Own Vulnerable Driver (BYOVD) technique to disable endpoint security controls prior to ransomware deployment. Notably, the Qilin ransomware group commonly leverages a malicious msimg32.dll file loaded via DLL side-loading, along with vulnerable drivers including rwdrv.sys and hlpdrv.sys, to gain kernel-level access and disable security processes. Similarly, Warlock ransomware has been observed exploiting the vulnerable NSecKrnl.sys driver to bypass security controls. The use of BYOVD has also been observed across ransomware campaigns associated with Akira, INC, Medusa, and other threat actors. 

What’s Notable and Unique 

• The Qilin ransomware group employs a sophisticated multi-stage infection chain, leveraging DLL side-loading (msimg32.dll) to execute malicious payloads directly in memory and evade traditional file-based detection. In DLL side-loading, a threat actor tricks a program into loading a malicious dynamic link library. The malware escalates privileges and uses signed but vulnerable drivers (rwdrv.sys and hlpdrv.sys) to bypass security controls, access system memory, and systematically disable endpoint defenses by terminating security processes and disabling monitoring callbacks at the kernel level. 

• Akira ransomware operators have also exploited the rwdrv.sys and hlpdrv.sys drivers. Additionally, Arete has observed threat actors leveraging multiple other drivers, including the vulnerable TrueSight.sys, to bypass security controls. 

• Meanwhile, Warlock ransomware operators disguised malicious activity by renaming rclone.exe to TrendSecurity.exe to appear legitimate. The file functioned as a loader, exploiting the vulnerable NSecKrnl.sys driver to disable security processes, while Group Policy Objects (GPOs) were leveraged to systematically disable security controls across the environment. 

Analyst Comments 

The BYOVD technique, employed by multiple known ransomware operators, reflects a broader shift toward pre-encryption defense evasion, including suppression of Windows telemetry, removal of monitoring callbacks, and abuse of legitimately signed but vulnerable drivers. This technique enables threat actors to evade detection, maintain persistence for extended periods, and maximize the operational impact of ransomware deployment across compromised environments. Organizations should implement strict driver control policies, such as Microsoft’s Vulnerable Driver Blocklist and application control mechanisms. Additionally, enforcing least privilege access, enabling multi-factor authentication (MFA), maintaining up-to-date patching, and continuously monitoring for anomalous driver and kernel-level activity can further reduce the risk of such attacks. 

Sources 

• Qilin EDR killer infection chain

• Web Shells, Tunnels, and Ransomware: Dissecting a Warlock Attack 

The threat landscape in March had a much more even distribution of threat groups than has been observed since the first half of 2025. Although Akira, Qilin, Play, and INC remained among the most active groups, Arete observed 21 unique ransomware and extortion groups in March, compared to only 15 in February. Akira and Qilin’s activity also declined from the previous month; in February, the two groups were responsible for almost half of all ransomware incidents, but in March they only comprised a little more than a quarter of all activity. Arete also observed activity from several emerging groups in the past month, including BravoX, NightSpire, Payouts King, and Securotrop.

 Figure 1. Activity from the top 5 threat groups in March 2026

Analysts at Arete identified several trends behind the threat actors perpetrating cybercrime activities:

• In March, threat actors actively exploited FortiGate Next-Generation Firewall appliances as initial access vectors to compromise enterprise networks. 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. Arete also observed Fortinet device exploitation involving various threat groups, with the Qilin ransomware group notably leveraging Fortinet device exploits.

  
  

• Phishing campaigns leveraging OAuth redirection and a resurgence of Microsoft Teams–based social engineering were also observed in March. In one campaign, attackers sent emails disguised as Microsoft Teams recordings or Microsoft 365 alerts, redirecting victims through legitimate OAuth endpoints to attacker-controlled pages hosting malicious ZIP payloads. A separate campaign has been ongoing since last year, in which attackers flood users’ inboxes with spam and impersonate IT support personnel to trick victims into initiating remote support sessions via tools like Quick Assist.

  
  

• Arete recently released its 2025 Annual Crimeware Report. Leveraging data and intelligence collected during ransomware and extortion incident response engagements, this report highlights notable trends and shifts in the threat landscape throughout 2025, including Akira’s unusually high activity levels in the second half of 2025, evolving social engineering techniques, and trends in ransom demands and impacted industries.

Sources

• Arete Internal

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