Multi-stage malware campaigns using fileless loaders, RATs, and evasion techniques
Multiple reports detail distinct, unrelated malware families and delivery chains rather than a single shared incident. One analysis covers NotOpenClaw, a Windows malware loader distributed via fake “OpenClaw” installers (including GitHub-hosted lures) and emphasizing VM/sandbox evasion; the sample analyzed was tagged with stealer-related indicators (e.g., VidarStealer) and was previously referenced in third-party reporting about fake OpenClaw installers deploying additional malware.
Separate research describes two different fileless/backdoor operations: HellsUchecker, a small native x64 backdoor delivered through a 10-stage chain beginning with a ClickFix fake Cloudflare CAPTCHA that tricks users into pasting an obfuscated Run command, using a LOLBin to fetch payloads over finger (TCP/79) and retrieving encrypted C2 configuration from a BNB Smart Chain smart contract ("EtherHiding"), culminating in an in-memory final payload using Hell’s Gate direct syscalls; and GhostWeaver, a fileless PowerShell RAT that selects persistence based on the installed AV product, uses TLS over TCP/25658, and relies on multiple DGA routines for delivery and C2. A separate brief reports the VOID#GEIST campaign delivering XWorm, AsyncRAT, and Xeno RAT via phishing, batch scripts from TryCloudflare domains, staged ZIP payloads, Python-based decryption/execution, and abuse of AppInstallerPythonRedirector.exe to facilitate additional RAT deployment.
Timeline
Mar 11, 2026
Analyst identifies NotOpenClaw fake AI installer malware
An analysis of a Windows sample posing as an OpenClaw AI installer identified a Rust-based loader dubbed NotOpenClaw, featuring extensive VM and sandbox evasion plus a staged PowerShell script that weakens Windows Defender and firewall protections. After patching anti-analysis checks, the analyst observed network activity, extracted limited IOCs, and linked the sample to prior fake OpenClaw installer activity.
Mar 11, 2026
Researchers observe active HellsUchecker ClickFix campaign
A 10-stage malware campaign using a fake Cloudflare Turnstile ClickFix lure was reported active, chaining finger.exe, Python bootstrapping, an MSI dropper, an EtherHiding loader, and the in-memory HellsUchecker backdoor. The operation used blockchain-hosted C2 configuration, anti-analysis checks, persistence via a BAT/MSBuild polyglot and Startup link, and direct-syscall injection.
Mar 10, 2026
Researchers publish GhostWeaver PowerShell RAT analysis
Researchers analyzed GhostWeaver, a fileless in-memory PowerShell RAT with antivirus-aware persistence, DGA-based C2, and sandbox evasion through the MintsLoader profiler. They also connected to two live C2 servers and observed both immediately deliver identical persistence payloads, and attributed the activity to TA582/UNC4108 linked downstream of the SocGholish infection chain.
Mar 10, 2026
Researchers document VOID#GEIST multi-RAT malware campaign
Researchers disclosed a modular malware campaign dubbed VOID#GEIST that begins with phishing emails and weaponized batch scripts hosted on TryCloudflare domains. The intrusion chain delivers XWorm, Xeno RAT, and AsyncRAT in stages, using PowerShell persistence, Python-based decryption, and process injection to improve flexibility and resilience.
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