A multi-stage phishing campaign emerged in early May 2026, impersonating LinkedIn and Indeed through typosquatted domains to deliver malicious payloads. The attack chain begins with fake CAPTCHA pages distributed via Google Ads, leveraging the legacy Finger protocol and native Windows utilities. Victims are tricked into executing commands that deploy portable Python runtimes (CPython or IronPython), which then execute in-memory shellcode. The campaign delivers CastleLoader, a Malware-as-a-Service framework using ChaCha20 and RC4 encryption for C2 communications, followed by a Python-based remote access trojan. The RAT provides interactive shell control, in-memory payload execution, and persistence mechanisms. The campaign represents an evolution of browser-based social engineering, combining Living-off-the-Land binaries with Python-based delivery to maintain a fileless footprint and evade detection through legitimate system utilities.
A new extortion group called Pink, tracked as cluster CL-CRI-1147, employs voice phishing and fake IT helpdesk impersonation to compromise organizations. The gang steals employee credentials, bypasses multi-factor authentication, and exfiltrates data from cloud storage platforms like SharePoint and OneDrive. Pink threatens to leak stolen information unless ransom demands are met, setting 72-hour deadlines. The group's data-leak site launched on May 31, 2026. This approach mirrors tactics popularized by Lapsus$, Scattered Spider, and ShinyHunters. Incident responders link Pink to The Com, a loosely connected network of English-speaking hackers and extortionists. Attackers use compromised victim accounts and internal Teams messages for extortion communications, reusing domains across multiple targets.
In April 2026, threat actors deployed Nimbus RAT against a legal industry target using Microsoft Teams voice phishing. The attack began with email bombing (282 emails in 90 minutes), followed by a fake IT helpdesk contact via Teams who convinced the victim to grant Quick Assist remote access. Within 20 minutes, a Java-based RAT was deployed that uses Google Drive and Google Sheets for command-and-control, making network traffic appear benign. Analysis of 1,540 suspicious Teams messages across 172 customer environments over 12 months revealed 65% originated from throwaway onmicrosoft.com tenants with IT-themed names. The malware bundles its own Java runtime, implements two credential theft mechanisms, and allows in-memory second-stage code execution. Post-compromise targeting included Signal Desktop attachments and Outlook mailboxes.
Through April 2026, Kimsuky deployed sophisticated malicious campaigns against South Korean military and corporate entities using tailored social engineering tactics including fake security software installation pages and spoofed Webex meeting pages leveraging legitimate meeting schedules. The threat actor introduced a novel JSONPing technique allowing distribution pages to verify in real time whether victims executed the payload via JSONP queries to localhost servers. Analysis revealed a new HttpSpy variant with a three-stage execution chain replacing the previous single-binary architecture, utilizing RC4 encryption and shared infrastructure indicators. Attribution was confirmed through code pattern overlaps, reused encryption keys, XAMPP certificate fingerprints, and preferred ASN usage consistent with historical Kimsuky operations targeting South Korea.
JINX-0164, a financially motivated threat actor active since mid-2025, has been conducting sophisticated campaigns against cryptocurrency organizations. The actor employs LinkedIn-based social engineering, posing as recruiters or business partners to deliver custom macOS malware including AUDIOFIX (a Python-based infostealer and RAT) and MINIRAT (a lightweight Go backdoor). Their operations focus on compromising developer endpoints to steal cryptocurrency wallet credentials, cloud secrets, and GitHub tokens. The attackers then pivot to CI/CD infrastructure, injecting malicious code into repositories to enable lateral movement. In April 2026, they executed a supply chain attack by trojanizing the npm package @velora-dex/sdk. The group masks activity using VPN services and demonstrates advanced capabilities including credential harvesting from password managers, browser extensions, and development tools.
A sophisticated spear-phishing campaign designated Operation Dragon Whistle has been identified targeting Changzhou University in China. The threat actor UNG002 leveraged highly contextual social engineering by impersonating official university communications regarding mandatory 2026 National Student Physical Fitness and Health Standards testing, which directly impacts graduation eligibility. The attack chain begins with a weaponized ZIP file containing a malicious LNK file disguised as a PDF document. Upon execution, it triggers a VBScript that simultaneously displays a legitimate-looking decoy document while deploying a multi-stage infection chain involving DLL sideloading via Bandizip.exe, anti-debugging techniques, and ultimately delivering a Cobalt Strike Beacon payload entirely in memory. The campaign demonstrates advanced evasion capabilities and utilizes Chinese cloud infrastructure hosted on Alibaba Cloud for command and control operations.
A new variant of SHub Stealer dubbed 'Reaper' targets macOS users through fake WeChat and Miro installers, employing sophisticated multi-stage delivery chains that spoof Apple, Google, and Microsoft services. The malware leverages the applescript:// URL scheme to bypass Terminal-based defenses, conducting extensive fingerprinting and anti-analysis checks before execution. Reaper harvests browser credentials, cryptocurrency wallets, developer configurations, iCloud data, and Telegram sessions. It includes an AMOS-style document theft module targeting files under 150MB with chunked uploads. The variant establishes persistence through a fake Google Software Update LaunchAgent and installs a backdoor for remote code execution. The infection specifically avoids CIS regions and employs extensive anti-analysis techniques including WebGL fingerprinting, VM detection, and DevTools interference.
A sophisticated ClickFix campaign was observed in April 2026 deploying PySoxy, a decade-old open-source Python SOCKS5 proxy tool, to establish encrypted proxy access on compromised hosts. The attack chain begins with social engineering that tricks users into executing obfuscated PowerShell commands, which then establishes scheduled task persistence and deploys an in-memory PowerShell-based command-and-control agent. Following domain reconnaissance activities, attackers deploy PySoxy to create a redundant encrypted access channel. The persistence mechanism continues attempting re-execution even after initial connections are blocked, demonstrating how single ClickFix executions can evolve into modular post-exploitation chains. This development represents a significant evolution from simple one-time execution to durable access with multiple redundant pathways, requiring comprehensive remediation beyond blocking initial callbacks.
In early May 2026, Instructure confirmed a breach affecting its Canvas learning platform after detecting unauthorized activity on May 1. ShinyHunters exploited the Free-For-Teacher account program, compromising the Canvas platform directly and exposing names, email addresses, student IDs, and private messages. The exposure window ran from April 30 to May 7, 2026. ShinyHunters claims 3.6 TB of data covering approximately 275 million users across 9,000 schools globally, including institutions in the US, Australia, and EU. This represents ShinyHunters' second attack against Instructure in eight months. Instructure shut down the Free-For-Teacher program permanently, rotated API keys and privileged credentials, and engaged forensic investigators. The stolen data enables personalized phishing campaigns targeting students and faculty, with attackers potentially having write access sufficient to deface login pages at multiple institutions.
KATARU is an IoT malware variant identified in 2026 that uses Telnet credential brute-forcing to infect devices. It combines traditional Mirai-style botnet features with multiple Linux local privilege escalation exploits and advanced persistence mechanisms across Linux and embedded platforms. The malware uses encrypted command and control communications and employs anti-analysis and decoy traffic techniques. Artifacts suggest AI-assisted development, including mismatched shellcode and untested cross-platform logic. It supports various DDoS attack methods and SSH brute-forcing.
BackgroundFix masquerades as a free image-editing tool but functions as a ClickFix social engineering lure. The fake service prompts users to verify they are human, copying malicious commands to their clipboard that invoke finger.exe to retrieve additional payloads. This chain delivers CastleLoader, which subsequently drops NetSupport RAT and a custom .NET stealer dubbed CastleStealer. The loader uses reflective PE injection, API hashing, and ChaCha20-encrypted C2 communications. CastleStealer targets browser credentials, cryptocurrency wallet extensions, and Telegram sessions through DPAPI decryption and Restart Manager APIs. The campaign leverages BYOI tactics with embedded Python interpreters and multiple shellcode stages. A notable implementation flaw exists where launch method 4 references regsrv32.exe instead of the correct regsvr32.exe, causing silent failures.
Bad actors exploited Kuse, a legitimate AI-based workplace application, to conduct a phishing campaign. Attackers leveraged a Vendor Email Compromise (VEC) to send malicious emails from a trusted vendor's compromised mailbox, establishing initial trust. The attack utilized Kuse's file-sharing features to host a fake blurred document with a Markdown file extension (.md) under the legitimate domain app[.]kuse[.]ai. Victims were presented with a fabricated document preview containing Spanish text prompting them to click a link. This redirected users to a fraudulent Microsoft login page designed to harvest credentials. The attack combined multiple social engineering techniques including domain trust exploitation, unusual file extensions to evade detection, and vendor relationship abuse to bypass security controls and user scrutiny.
Threat actors are exploiting AI agent skill formats as a novel attack vector, using convincingly packaged OpenClaw skills to distribute malicious payloads. The latest campaign employs pure social engineering, with skills containing no malicious code themselves but instead tricking users into downloading Windows binaries. The attack leverages a fake GitHub infrastructure hosting GachiLoader, which delivers Rhadamanthys infostealer through fileless injection. The operation uses two delivery mechanisms: Node.js Single Executable Applications and an Electron dropper, both converging on the same payload. GachiLoader employs sophisticated evasion techniques including anti-VM checks, sandbox detection, and privilege escalation, while using a Polygon blockchain smart contract as its C2 resolver for enhanced persistence and obfuscation.
A consumer-targeted credential theft operation uses DHL brand impersonation combined with a fake OTP verification mechanism to harvest passwords from victims. The attack employs an 11-step chain beginning with spoofed shipment notification emails, leading victims through a client-side generated OTP page that creates false trust, then directing them to a DHL-branded credential harvesting portal. The kit captures passwords alongside victim telemetry including IP address, device details, browser fingerprinting, and geolocation data. Exfiltration occurs through EmailJS, a legitimate client-side email service, sending stolen credentials to an attacker-controlled Tutamail address. The campaign concludes by redirecting victims to the legitimate DHL website to avoid suspicion, demonstrating how familiar workflows and brand trust can be weaponized without technical sophistication.
On April 23, 2026, Field Effect MDR identified AMOS Stealer malware delivered through a novel technique exploiting Cursor AI agent sessions running Claude Code. The attack employed social engineering to manipulate operators into prompting the AI agent to download and execute malicious AppleScript loaders. The heavily obfuscated scripts performed sandbox evasion checks, collected sensitive data including credentials, SSH keys, browser data, and cryptocurrency wallets, then exfiltrated compressed archives to remote servers within two minutes. The malware prompted users for local account credentials through fake macOS system dialogs, subsequently using elevated permissions to install persistent implants masquerading as legitimate system services. This delivery mechanism makes detection challenging as malicious commands blend with typical agentic coding behavior, representing an evolution in AMOS Stealer tactics beyond traditional SEO poisoning methods.
Google Threat Intelligence Group identified a sophisticated intrusion campaign by UNC6692 that combined persistent social engineering with custom malware. The attackers impersonated IT helpdesk personnel via Microsoft Teams, leveraging initial email spam campaigns to create urgency. Victims were tricked into downloading AutoHotKey scripts that installed SNOWBELT, a malicious browser extension establishing persistence through scheduled tasks. The modular SNOW ecosystem enabled deep network penetration: SNOWBELT provided initial access, SNOWGLAZE created encrypted WebSocket tunnels masking traffic as legitimate cloud communications, and SNOWBASIN functioned as a local backdoor for command execution. UNC6692 performed internal reconnaissance, escalated privileges by extracting LSASS memory, and used Pass-The-Hash techniques to access domain controllers. The operation culminated in exfiltration of Active Directory databases and credentials via LimeWire, demonstrating advanced tradecraft abusing legitimate clou...
Threat actors are leveraging fake CAPTCHA pages to trick victims into sending premium SMS messages as part of an international revenue share fraud (IRSF) scheme. Operating since at least June 2020, this campaign uses traffic distribution systems and social engineering to direct users through multi-stage fake verifications requiring SMS messages to international phone numbers across 17 countries with high termination fees. Each CAPTCHA step triggers messages to over a dozen destinations, generating over 60 SMS messages per victim costing approximately $30. The operation employs back button hijacking, sophisticated tracking cookies, and affiliate advertising networks to maximize reach while obscuring the fraud from detection. Both individual victims and telecommunication carriers suffer financial losses through this deceptive scheme.
A sophisticated ClickFix campaign was detected in mid-March 2026, beginning with a malicious webpage impersonating Booking.com's visual identity with a fake CAPTCHA. The attack leverages social engineering to trick victims into executing a PowerShell command that downloads and runs a script directly in memory. The JavaScript code automatically copies malicious commands to the clipboard and intercepts copy events. Once executed, the PowerShell dropper performs system fingerprinting, downloads a ZIP payload from a remote server, deploys it to user directories, establishes persistence through registry keys and scheduled tasks, and executes the final payload. The campaign demonstrates well-structured code with fallback mechanisms and real-time telemetry via Telegram, suggesting the use of a ready-to-use attack kit.
Attackers are leveraging the trusted reputation of Foxit PDF Reader, used by over 650 million people, to distribute malicious installers disguised as legitimate software. Rather than exploiting vulnerabilities, threat actors impersonate the vendor through fake installers with document-themed filenames that bypass user suspicion. When executed, these files display decoy passport images while downloading malicious MSI packages that deploy UltraVNC remote access tools disguised as GPU drivers. The attack establishes persistence through registry modifications and firewall exceptions, connecting to attacker-controlled infrastructure for complete remote system control. Telemetry indicates broad distribution across Germany, the United States, the United Kingdom, and Ukraine. This campaign demonstrates how brand impersonation combined with social engineering proves more effective than technical exploits, relying on user trust and behavioral patterns rather than software vulnerabilities.
A phishing campaign utilized a fraudulent Adobe-themed website to trick victims into downloading and executing ScreenConnect remote access software. Once initial access was established, threat actors conducted interactive operations deploying multiple malicious binaries including a credential harvesting tool named password.exe. The attackers also exploited the ms-phone URI handler to launch the Phone Link application, attempting to socially engineer victims into linking their mobile devices to potentially capture notifications, authentication prompts, and sensitive information. The attack demonstrates a multi-stage compromise focusing on persistence establishment, credential theft, and preparation for potential lateral movement across the victim's network infrastructure.
