< ciso
brief />
Tag Banner

All news with #remote access trojan tag

380 articles · page 18 of 19

RainyDay, Turian and PlugX Variant Abuse DLL Hijacking

🛡️ Cisco Talos describes an ongoing campaign in which Naikon-linked actors abused DLL search order hijacking to load multiple backdoors, including RainyDay, a customized PlugX variant and Turian. The report highlights shared loaders that use XOR and RC4 decryption with identical keys and an XOR-RC4-RtlDecompressBuffer unpacking chain. Talos notes the PlugX variant adopts a RainyDay-style configuration and includes embedded keylogging and persistence, with activity observed since 2022 targeting telecom and manufacturing organizations in Central and South Asia. Talos published IOCs and recommended mitigations for detection and prevention.
read more →

Oversized SVG Files Deliver AsyncRAT Across Latin America

🛡️ A recent campaign in Latin America leverages oversized SVG image attachments to deliver AsyncRAT by embedding the entire malicious payload inside the XML. Victims receive convincing, urgent emails impersonating judicial services, and interacting with the >10MB SVG loads a fake portal that triggers a password-protected ZIP download containing an executable and a DLL-sideloaded payload. ESET telemetry highlights a spike in activity, notably affecting Colombia, while attackers appear to use AI to generate unique, randomized SVGs to evade detection.
read more →

CountLoader Expands Use by Russian Ransomware Groups

🔒 Researchers have identified CountLoader, a multi‑language malware loader used by Russian ransomware affiliates and initial access brokers to deploy post‑exploit tools such as Cobalt Strike, AdaptixC2 and the commercial PureHVNC RAT. Appearing in .NET, PowerShell and JavaScript flavors, the loader has been observed in PDF phishing campaigns targeting Ukraine and employs LOLBins and multiple download/execution methods to evade detection. The JavaScript variant is most feature‑complete, offering diverse downloaders, execution paths and persistence via a Google‑update‑named scheduled task.
read more →

Malicious PyPI Packages Deliver SilentSync Remote RAT

⚠️ Zscaler ThreatLabz researchers discovered two malicious Python packages, sisaws and secmeasure, that were designed to deliver the SilentSync remote access trojan to Windows hosts. Both packages, uploaded by a user identified as 'CondeTGAPIS' and since removed from PyPI, contained downloader logic that retrieved a second-stage Python payload (via Pastebin) and executed code in memory. SilentSync can execute commands, harvest browser credentials and cookies, capture screenshots, and exfiltrate files, while offering persistence mechanisms across Windows, Linux and macOS.
read more →

TA558 Deploys AI-Generated Scripts to Install Venom RAT

⚠️Kaspersky tracked TA558, operating under the cluster known as RevengeHotels, using AI-generated JavaScript and PowerShell loaders in summer 2025 to deliver Venom RAT to hotels in Brazil and Spanish-speaking markets. Phishing emails in Portuguese and Spanish used reservation and job-application lures to coax users into running a WScript payload that chains to a PowerShell downloader fetching 'cargajecerrr.txt' and subsequent loaders. The Venom RAT, based on Quasar, includes data-stealing, reverse-proxy, persistence and aggressive anti-kill features aimed at harvesting payment card data from hotel systems and OTAs.
read more →

Chinese TA415 Abuses VS Code Remote Tunnel for Espionage

🔒 Proofpoint reported that a China-aligned threat actor tracked as TA415 conducted spear-phishing in July–August 2025, impersonating U.S. policy officials and the U.S.-China Business Council to target government, think tank, and academic personnel focused on trade and economic policy. The messages delivered password-protected archives on public cloud services that contained a Windows shortcut which executed a hidden batch script and an obfuscated Python loader named WhirlCoil while displaying a decoy PDF. The loader establishes a VS Code Remote Tunnel to enable persistent backdoor access, harvests system and user data, exfiltrates it via base64-encoded HTTP posts to free request-logging services, and establishes scheduled tasks (e.g., GoogleUpdate) for persistence.
read more →

Mustang Panda Uses SnakeDisk USB Worm to Deliver Yokai

🐍 IBM X-Force reports that China-aligned Mustang Panda is deploying a new USB worm, SnakeDisk, to propagate the Yokai backdoor against machines geolocated to Thailand. The actor also introduced updated TONESHELL variants (TONESHELL8/9) with proxy-aware C2 and parallel reverse shells. SnakeDisk abuses DLL side-loading and USB volume masquerading—moving user files into a subfolder and presenting a deceptive 'USB.exe' lure before restoring originals—to spread selectively on Thailand-based public IPs.
read more →

Phishing Campaigns Deploy RMM Tools via Multiple Lures

🔒 New phishing campaigns are delivering remote monitoring and management (RMM) software by using multiple realistic lures, security firms warn. Attackers spoof browser updates, meeting software installers, party e-invites and government forms to trick victims into running installers for ITarian (Comodo), Atera, PDQ, SimpleHelp and ScreenConnect. Some campaigns host payloads on trusted services such as Cloudflare R2 and may install multiple RMM tools in quick succession. Analysts caution RMM compromise can lead to ransomware and data theft and recommend endpoint detection, approved-tool enforcement and enhanced network controls such as browser isolation.
read more →

Fileless AsyncRAT infection leverages in-memory loaders

🔍 Security researchers at LevelBlue Labs identified an open-source Remote Access Trojan, AsyncRAT, being deployed via a multi-stage, fileless in-memory loader that avoids writing executables to disk. Attackers gained initial access through a compromised ConnectWise ScreenConnect client, executing a VBScript which invoked PowerShell to fetch two staged .NET assemblies. The first-stage assembly decodes payloads into byte arrays and uses reflection to run the secondary assembly directly in memory, while operators disabled AMSI and tampered with ETW to evade runtime detection. Persistence was achieved with a scheduled task disguised as "Skype Update," and the RAT used an AES-256 encrypted configuration to connect to a DuckDNS-based C2.
read more →

Fileless Malware Uses Legitimate Tools to Deploy AsyncRAT

🔍 Researchers uncovered a sophisticated fileless campaign that executes malicious code entirely in memory to deliver AsyncRAT. The attack began via a compromised ScreenConnect client and a VBScript that used WScript and PowerShell to download two payload blobs saved to C:\Users\Public\, which were never written as executables but loaded into memory via reflection. A .NET launcher (Obfuscator.dll) was used to orchestrate persistence, disable security logging and load the RAT, which exfiltrates credentials, browser artifacts and keystrokes.
read more →

Chinese APT Uses Fileless 'EggStreme' Against Military Firm

🔒 Bitdefender tracked a Chinese APT intrusion that used a novel, fileless framework dubbed EggStreme to compromise a Philippines-based military contractor. The multi-stage toolkit injects code directly into memory, leverages DLL sideloading and abuses legitimate Windows services for persistence, and delivers a gRPC-enabled backdoor, EggStremeAgent, with extensive reconnaissance and exfiltration capabilities. Bitdefender advises limiting use of high-risk binaries and deploying advanced detection and response to detect living-off-the-land operations and anomalous behavior.
read more →

AsyncRAT Delivery via ConnectWise ScreenConnect Abuse

⚠️ Cybersecurity researchers disclosed a campaign that abuses ConnectWise ScreenConnect remote sessions to deliver a fileless loader which ultimately executes the AsyncRAT remote-access trojan. Attackers use hands-on-keyboard activity to run a layered VBScript and PowerShell chain that loads obfuscated .NET assemblies and spawns AsyncClient.exe. Persistence is maintained via a scheduled task disguised as "Skype Updater," and stolen credentials, keystrokes, and wallet artifacts are exfiltrated to a DuckDNS command-and-control host.
read more →

Chinese APT Uses EggStreme Fileless Framework in Espionage

🛡️ Bitdefender attributed a campaign against a Philippines-based military contractor to a China-linked APT that deployed a previously undocumented fileless framework named EggStreme. The multi-stage operation begins with EggStremeFuel (mscorsvc.dll), which profiles systems, opens a C2 channel, stages loaders, and triggers in-memory execution of the core backdoor via DLL sideloading. EggStremeAgent functions as a central backdoor, injecting a session-specific keylogger (EggStremeKeylogger), communicating over gRPC, and exposing a 58-command toolkit for discovery, lateral movement, privilege escalation and data theft. An auxiliary implant, EggStremeWizard (xwizards.dll), provides reverse-shell access and resilient C2 options; Bitdefender warned that fileless execution and heavy DLL sideloading make detection and forensics difficult.
read more →

CHILLYHELL macOS Backdoor and ZynorRAT Cross-Platform RAT

🔍 Researchers have identified two malware strains: a modular macOS backdoor named CHILLYHELL and a Go-based cross-platform RAT called ZynorRAT. Jamf Threat Labs links CHILLYHELL to UNC4487, noting extensive host profiling, multiple persistence techniques, timestomping, and multi-protocol C2 over HTTP and DNS. The notarized CHILLYHELL sample (uploaded to VirusTotal on May 2, 2025) underscores that signed binaries can be malicious. Sysdig analysis shows ZynorRAT is managed via a Telegram bot and supports file exfiltration, screenshots, system enumeration, and persistence on Linux and Windows.
read more →

RatOn Android RAT Evolves with NFC Relay and ATS Capabilities

🛡️ ThreatFabric has identified a new Android remote access trojan, RatOn, that combines NFC relay attacks with automated money-transfer (ATS) and overlay capabilities to target cryptocurrency wallets and conduct device fraud. Attackers distribute droppers via fake Play Store listings (masquerading as a TikTok 18+ app) aimed at Czech and Slovak users, then request accessibility and device-admin permissions. RatOn deploys a third-stage NFSkate module for Ghost Tap NFC relays, presents overlay or ransom-style screens, captures PINs and seed phrases, records keystrokes, and exfiltrates sensitive data to attacker servers to drain accounts.
read more →

New Malware Campaigns: MostereRAT and ClickFix Risks

🔒 Researchers disclosed linked phishing campaigns delivering a banking malware-turned-RAT called MostereRAT and a ClickFix-style chain distributing MetaStealer. Attackers use an obscure Easy Programming Language (EPL), mutual TLS for C2, and techniques to disable Windows security and run as TrustedInstaller to evade detection. One campaign drops remote-access tools like AnyDesk and VNC variants; another uses fake Cloudflare Turnstile pages, LNK tricks, and a prompt overdose method to manipulate AI summarizers.
read more →

GPUGate: Malware Uses Google Ads and GitHub Redirects

🔒 Cybersecurity researchers have disclosed a sophisticated malvertising campaign that leverages paid search ads and manipulated GitHub commit URLs to redirect victims to attacker-controlled infrastructure. The first-stage dropper is a bloated 128 MB MSI that evades many online sandboxes and employs a GPU-gated decryption routine dubbed GPUGate, which aborts on systems lacking a real GPU or proper drivers. The campaign uses a lookalike domain (gitpage[.]app) and a VBScript-to-PowerShell chain that gains admin privileges, adds Microsoft Defender exclusions, establishes persistence, and stages secondary payloads for data theft.
read more →

MostereRAT Targets Windows with Layered Stealth Tactics

🔒 FortiGuard Labs has uncovered MostereRAT, a Remote Access Trojan targeting Microsoft Windows that uses layered evasion and persistence techniques. Written in Easy Programming Language, the malware deploys a multi-stage chain, uses mutual TLS for C2 communication, and can disable Windows Update and antivirus processes. The campaign, aimed largely at Japanese users, begins with phishing emails that lead to a malicious Word download and installs services running at SYSTEM-level, while deploying remote access tools such as AnyDesk and TightVNC.
read more →

MostereRAT Campaign Uses EPL, mTLS, and Legitimate RATs

🛡️ FortiGuard Labs identified a sophisticated phishing campaign that chains an Easy Programming Language (EPL) runtime with multi-stage payloads to deploy MostereRAT. The initial dropper, based on a wxWidgets sample, creates SYSTEM services and decrypts modules that run in memory while presenting social‑engineering prompts. Operators use mTLS‑protected C2 channels, disable and block security tooling via WFP filters, and install legitimate remote access tools such as AnyDesk and TightVNC to secure covert, persistent full access.
read more →

Noisy Bear Targets Kazakhstan Energy Firm with Phishing

🚨 Operation BarrelFire, attributed to a group Seqrite Labs calls Noisy Bear, targeted Kazakhstan's national oil company KazMunaiGas in May 2025 using tailored phishing. Attackers sent ZIP attachments containing an .LNK downloader, a decoy document, and a README in Russian and Kazakh instructing use of a fake KazMunayGaz_Viewer. The chain deployed a malicious batch, a PowerShell loader named DOWNSHELL, and a 64-bit DLL implant that executes shellcode to open a reverse shell. Infrastructure was linked to Russia-based bulletproof host Aeza Group, which has been sanctioned.
read more →