All news with #malware tag

🔒 This weekly recap highlights long-lived, stealthy intrusions and emerging tactics that are reshaping defender priorities. Chief among them, F5 disclosed a year-long breach involving the BRICKSTORM malware and stolen BIG-IP source material, while researchers uncovered new Linux rootkits such as LinkPro and campaigns abusing blockchain smart contracts for malware delivery. The report urges inventorying edge devices, prioritizing patches, and improving detection, baselining, and intelligence sharing.

🔐 ClickFix attacks trick users into copying and executing malicious code from a webpage—often presented as a CAPTCHA or a prompt to 'fix' an error—so the payload runs locally without a download. Researchers link the technique to Interlock and multiple public breaches and note delivery has shifted from email to SEO poisoning and malvertising. The articles says clipboard copying via JavaScript and heavy obfuscation let these pages evade scanners, and that traditional EDR and DLP often miss the attack. Push Security recommends browser-based copy-and-paste detection to block attacks before the endpoint is reached.

🔍 Cybersecurity researchers uncovered a coordinated operation that used 131 rebranded Chrome extensions—about 20,905 active users—to inject automation code into WhatsApp Web and conduct large-scale spam campaigns targeting Brazilian users. Socket found the add-ons share a common codebase, design patterns, and infrastructure and are primarily published under WL Extensão variants. The extensions pose a high spam risk by automating bulk outreach and scheduling to evade WhatsApp rate limits and violate Chrome Web Store policies.

🔒 Microsoft Threat Intelligence has revoked more than 200 code-signing certificates that were fraudulently used to sign counterfeit Microsoft Teams installers delivering a persistent backdoor and ransomware. The campaign, tracked as Vanilla Tempest (also known as Vice Spider/Vice Society), employed SEO poisoning and malvertising to lure users to spoofed download sites hosting fake MSTeamsSetup.exe files that deployed the Oyster backdoor and ultimately Rhysida ransomware. Microsoft says the actor abused Trusted Signing and services such as SSL.com, DigiCert and GlobalSign to sign malicious binaries. A fully enabled Microsoft Defender Antivirus detects and blocks these threats, and Microsoft provides guidance through Microsoft Defender for Endpoint for mitigation and investigation.

🔒 Seqrite Labs uncovered a new .NET implant named CAPI Backdoor linked to a phishing campaign targeting Russian automobile and e-commerce organizations. The attack leverages a ZIP archive containing a decoy Russian tax notice and a Windows LNK that loads a malicious adobe.dll via the legitimate rundll32.exe. The backdoor gathers system and browser data, takes screenshots, and communicates with a remote C2 for commands and exfiltration. Persistence is achieved through scheduled tasks and a Startup LNK.

🔐 Cisco Talos reports that a North Korean-linked threat cluster has blended features of its BeaverTail and OtterCookie JavaScript malware families, with recent OtterCookie variants adding keylogging, screenshot capture, and clipboard monitoring. The intrusion chain observed involved a trojanized Node.js application called Chessfi and a malicious npm dependency published on August 20, 2025 that executed postinstall hooks to launch multi-stage payloads. Talos tied the activity to the Contagious Interview recruitment scam and highlighted continued modularization and abuse of legitimate open-source packages and public Git hosting to distribute malicious code.

⚠️ Google Threat Intelligence Group has linked a North Korean threat actor to EtherHiding, a technique that embeds malicious JavaScript inside smart contracts so the blockchain functions as a resilient command-and-control server. Tracked as UNC5342, the actor used EtherHiding within an elaborate social-engineering campaign to deliver JADESNOW and a JavaScript variant of INVISIBLEFERRET, leading to multiple cryptocurrency heists. The campaign targets developers via fake recruiters and deceptive coding tests on Telegram and Discord.

🔍 FortiGuard Labs observed a January 2025 campaign that began with Winos 4.0 infections in Taiwan and evolved into a cross‑regional HoldingHands operation affecting China, Taiwan, Japan, and Malaysia. The actor uses phishing PDFs, cloud-hosted and bespoke domains, and multi-stage loaders that leverage Windows Task Scheduler to evade detection. Shared infrastructure, reused code (including digital signatures and debug paths), and repeated JavaScript download scripts link disparate samples, and Fortinet provides detections, IOCs, and mitigation guidance.

🔒 Microsoft disclosed it revoked more than 200 certificates after a threat actor tracked as Vanilla Tempest used them to fraudulently sign malicious binaries, including fake Microsoft Teams installers that delivered the Oyster backdoor and led to Rhysida ransomware deployments. The activity was detected in late September 2025 and disrupted earlier this month, and Microsoft has updated security solutions to flag the associated signatures. The actor abused SEO poisoning and bogus download domains impersonating Teams to distribute trojanized installers. Users are advised to download software only from verified sources and to avoid suspicious links or ads.

🔒 Microsoft disrupted a campaign by the financially motivated group Vanilla Tempest (also tracked as VICE SPIDER/Vice Society) after revoking over 200 code signing certificates used to sign malicious Microsoft Teams installers. The attackers used malvertising and SEO-poisoned domains mimicking Teams to distribute fake MSTeamsSetup.exe files that deployed the Oyster backdoor. The intervention curtailed a wave of Rhysida ransomware launches.

🪙 Google Threat Intelligence Group links a financially motivated actor, UNC5142, to widespread compromises of WordPress sites that leverage EtherHiding and on-chain smart contracts to distribute information stealers such as Atomic, Lumma, Rhadamanthys and Vidar. The campaign injects a multi-stage JavaScript downloader (CLEARSHORT) into plugins, themes and databases to query malicious BNB Smart Chain contracts, which return encrypted landing pages that use ClickFix social engineering to trick Windows and macOS users into executing stealer payloads. Google flagged roughly 14,000 infected pages through June 2025, and observed a move to a three-contract proxy-like architecture since November 2024 that improves agility and resistance to takedown.

🔒 Google Threat Intelligence Group (GTIG) reports that a DPRK-aligned threat actor tracked as UNC5342 has employed EtherHiding since February to host and deliver malware via smart contracts on Ethereum and the BNB Smart Chain. Campaigns begin with fake technical interviews that trick developers into running a JavaScript downloader named JADESNOW, which fetches a JavaScript build of InvisibleFerret for in-memory espionage and credential theft. The method offers anonymity, takedown resistance, and low-cost, stealthy payload updates.

🧩 GTIG reports that DPRK-linked UNC5342 has adopted EtherHiding, using smart contracts on public blockchains to store and deliver malicious JavaScript payloads. The actor leverages social engineering—fake recruiter lures and technical interviews—to deploy the JADESNOW downloader, which fetches and decrypts on-chain payloads and stages the Python backdoor INVISIBLEFERRET. Google recommends enterprise controls and Chrome management policies to disrupt this resilient, decentralized C2 method.

🔐 Since late 2023, Mandiant and the Google Threat Intelligence Group tracked UNC5142, a financially motivated cluster that compromises vulnerable WordPress sites to distribute information stealers. The actor's CLEARSHORT JavaScript loader uses Web3 to query smart contracts on the BNB Smart Chain that store ABIs, encrypted landing pages, AES keys, and payload pointers. By employing a three-contract Router-Logic-Storage design and abusing legitimate hosting (Cloudflare Pages, GitHub, MediaFire), operators can rotate lures and update payload references on-chain without changing injected scripts, enabling resilient, low-cost campaigns that GTIG found on ~14,000 injected pages by June 2025 and which showed no on-chain updates after July 23, 2025.

🛡️ Researchers disclosed a campaign, Operation Zero Disco, that exploited a recently patched SNMP stack overflow (CVE-2025-20352) in Cisco IOS and IOS XE devices to deploy Linux rootkits on older, unprotected switches. The attackers achieved remote code execution and persistence by installing hooks into IOSd memory and setting universal passwords that include the string "disco." Targets included legacy 3750G and 9300/9400 series devices lacking EDR protections.

🔍 Talos uncovered a campaign linked to the DPRK-aligned cluster Famous Chollima that used a trojanized Node.js package and a malicious VS Code extension to deliver merged BeaverTail and OtterCookie tooling. The combined JavaScript payloads include a newly observed keylogger and screenshot module alongside clipboard theft, targeted file exfiltration, remote shell access, and cryptocurrency extension stealing. Indicators, C2 addresses, Snort/ClamAV detections, and mitigation guidance are provided.

🔔 This week’s ThreatsDay bulletin highlights a historic U.S. DOJ seizure of roughly $15 billion in cryptocurrency linked to an alleged transnational fraud network, alongside active commodity malware, phishing-as-a-service, and novel abuses of legitimate tools. Notable incidents include the Brazil-distributed Maverick banking trojan spread via a WhatsApp worm, consumer-grade interception of geostationary satellite traffic, and UEFI BombShell flaws enabling bootkit persistence. Priorities: identity resilience, patching, and monitoring of remote-access and cloud services.

🛡️ Minecraft mods can enhance gameplay but also serve as vectors for malware. This article explains how threat actors disguise Trojans, infostealers, ransomware and cryptominers as mods or cheat tools and distribute them via GitHub, mod repositories and forums. It outlines practical precautions — sourcing mods from trusted repositories, checking developer reputation and file types, using non-admin accounts, backups and security software — and steps to take if a mod is suspected malicious.

⚠ The phishing campaign impersonates LastPass and Bitwarden, sending convincing emails claiming breaches and urging users to install a 'more secure' desktop app. The distributed binary installs the legitimate Syncro MSP agent, which then deploys ScreenConnect remote-access software to give attackers persistent control. Cloudflare is blocking the malicious landing pages, and vendors confirm no breaches occurred.

⚠️ Koi Security disclosed a coordinated campaign by a group dubbed TigerJack that published malicious extensions to the Visual Studio Code Marketplace and the OpenVSX registry to exfiltrate source code, deploy cryptominers, and maintain remote access. Two popular packages — C++ Payground and HTTP Format — accumulated over 17,000 downloads before removal from Microsoft's store, yet variants remain active on OpenVSX. Researchers warn that the most advanced builds fetch and execute remote JavaScript, allowing attackers to push new payloads without republishing and evading static scanners.