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HVNC Backdoor Targets LATAM Organizations with Fake Tax and DocuSign Lures

A custom HVNC backdoor is targeting Latin American financial organizations via fake DocuSign and NFe tax-document lures, giving attackers hidden persistent remote access.

ANY.RUN researchers analyzed a multi-stage phishing campaign delivering a custom HVNC backdoor to banking and financial organizations in Latin America. The chain starts with fake DocuSign and NFe tax-document pages that serve per-visitor ZIP archives, followed by an LNK dropper, an NSIS loader, and a 64-bit backdoor masquerading as Windows Update Assistant. The implant provides hidden remote desktop control, keystroke monitoring, Firefox data theft, Startup-folder persistence, and EDR-aware behavior, communicating over TCP/27015.

ANY.RUN · 8d agoMalware in the wild

New SLEEPWALKER Backdoor Waits for One Crafted Packet, Then Runs Its Own Bytecode

A new Windows backdoor dubbed SLEEPWALKER hides as ESET Management Agent's dpapi.dll, waits for a crafted network packet, then executes custom 23-instruction bytecode.

Researcher Dominik Reichel documented SLEEPWALKER, an unsigned 59,904-byte 64-bit Windows DLL that side-loads into ESET Management Agent's ERAAgent.exe while impersonating dpapi.dll. The implant monitors every network interface indefinitely for a specifically crafted trigger packet, then executes commands written in a custom 23-instruction bytecode language over six transports, including TCP, UDP, ICMP, SMB named pipes, raw promiscuous capture, and VMware VMCI. It has no embedded infrastructure, makes no outbound connections of its own, and requires prior local administrator access to install; no victims, attribution, or in-the-wild deployment are confirmed. Reichel assesses the design as consistent with a targeted, well-resourced operation, while ESET calls the scenario's security relevance negligible since it provides no new access path.

The Hacker News · 12d agoMalware1

Chinese-Speaking Hackers Use Noodle RAT Backdoor to Spy on Windows and Linux Systems

Chinese-speaking actors use cross-platform Noodle RAT backdoor to maintain covert access to Windows and Linux systems across Asia-Pacific.

Noodle RAT (also ANGYREBEL/Nood RAT) has been active since at least mid-2016 and was long misidentified as Gh0st RAT or Rekoobe variants until Trend Micro and Cyberint classified it as a distinct multi-platform family. The Windows build (Win.NOODLERAT) is an in-memory modular shellcode backdoor delivered via MULTIDROP and MICROLOAD loaders, while the Linux build supports reverse shells, SOCKS tunneling, and cron persistence after web shell or public-facing service exploitation. It has appeared in intrusions in Thailand, India, Japan, Malaysia, and Taiwan and is linked to Iron Tiger, Calypso APT, Rocke, and Cloud Snooper campaigns spanning espionage and cybercrime. Recently discovered Linux builders 1.0.1 and 1.0.2 indicate the toolkit remains actively maintained.

GBHackersupdated · 13h agofirst · 15h agoMalware in the wild 2 sources1

Bisonal Malware Used in Attacks Against Russia and South Korea

Unit 42 details a Bisonal malware variant, active since 2014, targeting Russian and South Korean defense organizations via PDF-disguised spearphishing emails.

In early May, Unit 42 discovered a campaign delivering a Bisonal malware variant against at least one Russian communications security and cryptography company and one unidentified organization in South Korea. The variant, in the wild since at least 2014, introduces a new C2 cipher and rewritten networking and persistence code, with only 14 samples collected to date. Attackers spoofed Russian state corporation Rostec in spearphishing emails carrying an executable disguised with a PDF icon; the dropper decrypts an RC4-encrypted DLL and establishes persistence via a registry Run key. Bisonal has been used since 2013 against government, military, and defense targets in South Korea, Russia, Japan, and India, alongside successors Bioazih and Dexbia.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wild

When scanners miss the attack: how Cloudflare Client-Side Security protects storefronts

Cloudflare's Page Shield ML uncovered four malicious JavaScript campaigns on storefronts, including affiliate fraud and a remote-backdoor script, that VirusTotal and URLScan missed.

Cloudflare's Page Shield ML detected four client-side JavaScript operations (eight payloads) in live traffic on online storefronts, enabling affiliate commission hijacking, clickless affiliate theft via hidden iframes, user tracking with a remote-code backdoor, and cloaking of paid mobile visitors. Seven of the eight payloads were absent from VirusTotal and URLScan returned no malicious verdict for any, including a Lnkr-family payload indexed unclassified for roughly 2.5 years. Detection relies on a graph neural network over JavaScript syntax trees, an LLM second opinion on Workers AI, and a frontier-model ensemble voting across benign, magecart, other malware, and cryptomining labels.

Cloudflare Blog · 7h agoMalware in the wild

ValleyRAT: When Legitimate Software Becomes a Malware Delivery Tool

Kaspersky details ValleyRAT delivered via trojanized QN Wallpaper using DLL sideloading, tied to Silver Fox and hitting 1,500+ users in China and India.

Kaspersky found a malicious installer abusing a modified version of the legitimate QN Wallpaper adware application to deliver the ValleyRAT backdoor via DLL sideloading of libcef.dll. The installer masquerades as DingTalk, Chrome or Tencent Meeting software, creates persistence, disables Windows Defender via the DisableAntiSpyware registry key, and loads AES-encrypted payloads. ValleyRAT collects keystrokes, clipboard contents and screenshots plus system details, can download additional modules, and resists removal by injecting into svchost.exe or marking its process critical. The campaign was detected over 100,000 times in 2026, affecting more than 1,500 users mainly in China and India, and is attributed to Silver Fox with both espionage and financial motives.

Security Affairs · 16d agoMalware in the wild

PEEP Turns Chrome and Edge Into Post-Compromise Backdoors for Host Command Execution

SOCRadar disclosed PEEP, a post-exploitation Chromium extension toolkit that turns Chrome and Edge into host-level backdoors via native messaging and C2 polling.

SOCRadar researchers detailed PEEP, a Chromium-based post-exploitation toolkit masquerading as a 'Smart Bookmarks' extension injected directly into Chrome and Edge profiles by forging Secure Preferences integrity values, bypassing Web Store checks. A native-messaging host binary (nm_host.exe) extends the browser agent to host-level command execution, file management, credential theft, and session hijacking, while the extension polls C2 endpoints at 206.237.30.232 or xfjcc.fun every 30 seconds over plaintext HTTP and exfiltrates browsing history, cookies, and tab metadata. PEEP is derived from the open-source RedExt red teaming framework, adds PowerShell persistence scripts, and includes a Linux-targeting Python script, suggesting cross-platform intent. The activity is unattributed but contains Chinese-language artifacts; a C2 /health endpoint showed 34 agent entries and 10 active sessions.

The Hacker News · 9d agoMalware in the wild1

ValleyRAT Backdoor Hides in Signed Adware That Users Add to Antivirus Exclusions

Silver Fox distributes ValleyRAT via signed QN Wallpaper adware, sideloading a malicious libcef.dll into a trusted process to evade defenses.

Kaspersky reports the Silver Fox threat actor disguising the ValleyRAT backdoor (Winos 4.0) inside a modified, signed copy of the QN Wallpaper adware tool, using DLL sideloading to run within a trusted process. The installer disables Windows Defender via the DisableAntiSpyware registry key, adds autorun entries, and elevates via runas when needed; ValleyRAT steals keystrokes, clipboard data, and screenshots and can mark its process critical to trigger BSOD if killed. Kaspersky recorded more than 100,000 ValleyRAT detections affecting over 1,500 unique users in 2026, mostly in China and India, with prior campaigns against Japan, India, and Russia.

The Hacker News · 16d agoMalware in the wild

C2Looper: A New Backdoor Likely Tied To Ransomware With GitHub C2

Zscaler ThreatLabz identified C2Looper, a new Rust-based backdoor likely tied to ransomware actors and delivered via ClickFix chains, using GitHub for C2.

In July 2026, Zscaler ThreatLabz identified C2Looper, a new Rust-based backdoor family. The malware supports arbitrary command execution, reconnaissance, and deployment of second-stage payloads, and uses GitHub as its command-and-control channel. ThreatLabz assesses with low-to-medium confidence that it is delivered through multi-stage ClickFix infection chains and is likely leveraged by a ransomware-related threat actor. The analysis covers multiple C2Looper variants, their network protocols, and capabilities.

Zscaler ThreatLabz · Aug 17, 2026Malware in the wild1

BambooToken malware controls Windows and Linux systems via MQTT

Lumen Black Lotus Labs exposes BambooToken, a China-aligned malware framework using MQTT C2 to backdoor Windows and Linux systems at roughly a dozen enterprises.

Lumen's Black Lotus Labs documented BambooToken, a previously unknown malware framework active since at least 2023 that adopted MQTT for command-and-control in 2024-2025 variants targeting Windows and Linux. Infection occurs via DLL side-loading through digitally signed Tendyron OnKey USB-token software or an impersonated Kingsoft Office installer; dead code suggests keylogging, clipboard theft, audio/webcam capture, and screenshot modules. Telemetry identified roughly a dozen compromised entities, mostly in Asia and South America, including a Hong Kong GitLab server and possibly users of the SpeedCN VPN service. Targeting patterns are consistent with China-aligned operations, though no attribution to a known cluster was made.

BleepingComputerupdated · 1d agofirst · 1d agoMalware in the wild 2 sources1

ThreatsDay: 296K IoT Botnet, 100+ Water Systems Targeted, SharePoint RCE Chain + 27 New Stories

Weekly ThreatsDay bulletin details a ShinyHunters-style social engineering hit on ReliaQuest, the 296,000-device Dysphoria IoT botnet, and several new malware families.

ReliaQuest confirmed a social engineering attack on August 22, 2026, in which an attacker used a fake SSO page and MFA push approval to gain brief view-only access to an identity dashboard, with tactics matching ShinyHunters, which has since listed the firm on its leak portal. The Shadowserver Foundation reported the Dysphoria botnet has compromised nearly 296,000 IoT devices for DDoS attacks and recently added residential proxy capability. Cisco Talos documented JWR, an operator-driven phishing-as-a-service framework linked to The Outsider that harvests credentials, identity documents, and 2FA codes over an encrypted WebSocket. New malware coverage includes the Octagon Android fraud bot ($1,400/month), the C2Looper Rust backdoor delivered via ClickFix, and the Aeternum loader that moved C2 to the Polygon blockchain.

The Hacker News · 15d agoMalware in the wild

ValleyRAT masquerading as adware

Kaspersky reports threat actors distributing the ValleyRAT backdoor disguised as adware, tracing the infection chain to the final payload.

Kaspersky researchers analyzed a campaign distributing the ValleyRAT backdoor under the guise of adware. The write-up documents the complete infection chain, from the malicious installer through deployment of the final backdoor payload. ValleyRAT is a remote access tool typically used by criminal actors for surveillance and data theft.

Kaspersky Securelist · 16d agoMalware in the wild

UBoatRAT Navigates East Asia

Unit 42 discovers UBoatRAT, a new custom RAT targeting South Korean and video-game industry personnel, delivered via Google Drive with GitHub-based C2 and BITS persistence.

Unit 42 identified UBoatRAT, a new custom remote access trojan first found in May 2017, whose initial version used a public Hong Kong blog service and a compromised Japanese web server for command and control. The latest variants target personnel or organizations related to South Korea or the video games industry, are delivered through Google Drive, and masquerade as Microsoft Word, Excel, or folder icons. The RAT checks for virtualization software and domain join, retrieves its C2 address from a Base64-encoded string in a GitHub-hosted file, uses a custom XOR-encrypted C2 protocol, and maintains persistence via Windows Background Intelligent Transfer Service (BITS) jobs that survive reboots.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wild1

Hackers Abuse YouTube Gaming Channels and SEO Poisoning to Deploy RATs and Chrome Hijacker

Unit 42 exposed CL-CRI-1171, a pay-per-install operation using YouTube gaming channels and SEO poisoning to deliver RATs and a Chrome hijacker.

Palo Alto Networks Unit 42 identified over 10,000 OfferLoader samples and 11 YouTube channels pushing trojanized installers via gaming lures and SEO-poisoned searches for tools like WinDirStat and Bluetooth drivers. Trojanized Inno Setup installers spawn three payload branches: Insomnia RAT (dual Node.js/Python backdoor that disables Microsoft Defender), ARKTunnel (undocumented RAT hiding its payload in a bitmap image and tunneling TCP/UDP), and Docro Hijacker (alters Chrome protected preferences to hijack search and affiliate links). The pay-per-install model sells each infection to multiple buyers, reaching gamers as well as corporate and government endpoints.

Cyber Security News · 2d agoMalware in the wild1

SloppyRAT: A New Tool For Ransomware Attacks

Zscaler details SloppyRAT, a new DLL backdoor delivered via ClickFix lures that stages CastleLoader and CastleRAT ahead of ransomware attacks.

Zscaler ThreatLabz analyzed SloppyRAT, a DLL-based backdoor distributed via ClickFix lures that abuses finger.exe over TCP port 79 to download a batch script. The malware copies curl.exe to download IronPython 3.4.2 from GitHub and executes zlib-compressed Base64-encoded Python to deploy CastleLoader and CastleRAT, then reflectively loads SloppyRAT in memory. It hinders analysis using XOR stack-string obfuscation, a modified affine cipher with modulus 127, and 13 runtime-decrypted code blocks, while communicating with C2 over a reverse SOCKS channel.

Zscaler ThreatLabzupdated · 5d agofirst · 6d agoMalware in the wild 3 sources

BraZetsu Malware Turns Compromised Windows Hosts Into Criminal Marketplace Inventory

Group-IB details BraZetsu, a modular Python Windows malware that monetizes compromised-host access through the Infected Marketplace for initial access brokers.

Group-IB attributes BraZetsu to the Exilware threat actor, believed to be native Portuguese speakers targeting Iberian and Latin American e-commerce, financial, industrial, and law enforcement victims. The framework, first observed in early May 2026, uses generative AI for data triage and target prioritization, steals browser histories and digital certificates, and hunts Brazilian CNAB financial remittance files. Access to compromised hosts is sold on the Infected Marketplace from roughly $5.80, letting buyers remotely deploy secondary payloads over WebSocket-linked infrastructure. Some samples evaded detection on VirusTotal; delivery likely uses VBS loaders from a domain also used to distribute the Ousaban banking trojan.

The Hacker News · 13d agoMalware in the wild

BambooToken: The Malware That Speaks MQTT to Stay Under the Radar

Lumen's Black Lotus Labs uncovered BambooToken, a Windows and Linux malware family using MQTT broker-based C2 and DLL sideloading across Asia since February 2023.

Lumen Black Lotus Labs identified BambooToken, a multiplatform malware family that exchanges commands through MQTT brokers so infected hosts never contact the C2 server directly, active from at least February 2023 through July 2026. The Windows variant sideloads via Tendyron's OnKey hardware-token software used in Chinese banking and government, or impersonates Kingsoft Office, without either vendor's signing certificate being compromised; a Linux build appeared by December 2025 with shell, file transfer, and system information commands. Victims include MikroTik and DrayTek routers in Singapore, Cambodia, and Vietnam reached after internet-wide SNMP scanning, and Lumen cannot attribute the family to any known actor.

Security Affairs · 7h agoMalware in the wild

WordlistLoader Delivers Amatera via ClickFix, SynkLoader Phishes Windows Passwords

Gen Digital details WordlistLoader delivering Amatera Stealer via ClickFix and EtherHiding, while SynkLoader phishes Windows credentials through Microsoft Teams.

Gen Digital identified WordlistLoader, an intermediate stage that reconstructs shellcode encoded as plain English words (or 16-byte UUID chunks) and loads Amatera Stealer 4.3.3-alpha1, delivered through ClearFake ClickFix prompts on compromised websites. The chain uses EtherHiding to fetch JavaScript from a blockchain smart contract, hidden cmd.exe via conhost, WebDAV-mounted shares with rundll32 execution, and ETW bypass via hardware breakpoints. The stealer adds hardened WoW64 syscalls, Heaven's Gate indirect-syscall trampolines and a redesigned application-bound encryption bypass. Separately, Expel observed SynkLoader distributed via Microsoft Teams phishing impersonating IT service desks, installing an MSI from Azure blob storage and serving a fake lock screen to capture credentials.

The Hacker News · 21d agoMalware

Android Car Malware Spreads Through Built

Kaspersky found MoYu Group malware infecting DoFun Android car head units via firmware updaters, enabling ad fraud and proxy botnet operations.

Kaspersky discovered in June 2026 the first documented malware specifically infecting Android-based car head units, spread through the built-in updater (TWCore) of DoFun head unit firmware via a dropper dubbed JarService. The multi-stage implant supports nine commands enabling unwanted ads, ad fraud, and additional module downloads, and installs the zhima reverse proxy module. The campaign is attributed with high confidence to the MoYu Group behind the BADBOX ad fraud and residential proxy scheme; the distribution issue was fixed after responsible disclosure.

The Hacker News · 22d agoMalware in the wild

Android car head units infected with proxy botnet malware through built-in software updaters

Kaspersky found malware delivered via car head unit updaters, attributed to the MoYu Group's BADBOX operation, recruiting devices into a proxy botnet.

Kaspersky discovered malware delivered through the built-in TWCore system updater in Android-based car head units running DoFun infotainment firmware, turning devices into ad-fraud tools and nodes in a proxy botnet. The three-stage infection chain (JarService dropper, loader, and final payload supporting nine commands) installs the zhima reverse-proxy module, which Nokia's Deepfield team independently found on TV set-top boxes. Kaspersky attributes the operation with high confidence to the MoYu Group, linked to the BADBOX supply-chain botnet first identified by HUMAN Security in 2023. DoFun closed the gap after Kaspersky's responsible disclosure.

Help Net Security · 24d agoMalware in the wild

TWINLOOT Abuses SharePoint and Teams to Steal Credentials and Move Across Networks

Ontinue disclosed TWINLOOT, a Python implant hiding C2 in SharePoint dead drops and Teams TURN relays, harvesting credentials and pivoting via reverse SOCKS5.

Ontinue's Cyber Defense Center identified TWINLOOT during a July 2026 campaign investigation: a modular, PyArmor-hardened Python implant (a 39 MB bootstrap-fat.pyc loader) whose entire C2 infrastructure lives inside trusted Microsoft services. Tasking flows through SharePoint Online file dead drops polled every 15 seconds via the Microsoft Graph API, while interactive operator access uses WebRTC DataChannels relayed by Microsoft Teams TURN servers; Graph traffic is driven by the victim's own headless Edge browser. The implant harvests Windows credentials with fake lock screens, offers a reverse SOCKS5 pivot for lateral movement to SMB, RDP, WinRM, and MSSQL, executes commands, and persists on hosts. Initial access is assessed to be Teams social engineering masquerading as IT support, prompting a PowerShell command to download the payload.

The Hacker News · 29d agoMalware

Analysis of Smoke Loader in New Tsunami Campaign

Fake Japanese Meteorological Agency tsunami warning emails delivered Smoke Loader and AzoRult malware to steal credentials from targets in Japan.

A fake tsunami warning email impersonating Japan's Meteorological Agency asked recipients to click a link on a registered fake agency domain, delivering the commodity loader Smoke Loader to targets in Japan. Smoke Loader, active since 2011, is modular, and its payloads have included banking trojans, ransomware, cryptominers, password stealers, and PoS malware; the campaign later also deployed AzoRult. New samples add junk-jump obfuscation, encrypted network traffic and payload files, a unique machine ID used for tracking and encryption, and PROPagate injection into explorer.exe, with persistence via a Startup folder shortcut and RC4-encrypted C2 communication.

Palo Alto Unit 42 · Aug 17, 2026Malware in the wild