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ClearFake Deploys Crypto Stealer That Uses Vulnerable Driver to Kill EDR Security Tools

Cisco Talos details ClearFake's fake-CAPTCHA chain deploying ZigCryptoStealer with a BYOVD attack that kills EDR processes, observed at a Ukrainian government organization in April 2026.

ClearFake compromises websites, injects JavaScript via a malicious Cloudflare Worker, retrieves instructions from BNB Smart Chain contracts (EtherHiding), and presents a fake Google CAPTCHA that tricks Windows users into pasting a command that loads a remote library over WebDAV via rundll32. The crypto-stealer branch uses DLL side-loading with a signed Chrome component to launch ZigCryptoStealer, which hijacks clipboard cryptocurrency addresses, alongside a signed but vulnerable Windows driver used in a BYOVD attack to terminate EDR processes. A parallel branch delivers Amatera secondary payloads that install a hidden remote-access client providing operator desktop control, with Cisco Talos tracking the remote-loader activity as UAT-10820. Talos observed unusual remote library execution at a Ukrainian government organization in April 2026 and assesses the attacks are part of a broader theft operation rather than a single targeted campaign.

Cyber Security News · 7d agoMalware in the wild1

Stately Taurus Activity in Southeast Asia Links to Bookworm Malware

Unit 42 links Stately Taurus APT activity in ASEAN region and Myanmar to the decade-old Bookworm malware family via infrastructure overlaps.

Unit 42 connected Stately Taurus (aka Mustang Panda) espionage activity targeting ASEAN-affiliated organizations and Myanmar to the Bookworm malware family, first published in 2015. Earlier attacks delivered the PubLoad stager via DLL sideloading, with a PubLoad variant communicating with C2 at 123.253.32[.]15 while mimicking Windows Update URLs. Three previously unreported loader samples from 2021-2022 used UUID-decoded shellcode loaded via heap allocation and API callbacks, ultimately decrypting and loading Bookworm DLLs. A ToneShell backdoor variant shared debug paths with Bookworm loaders, and the January 2024 CSIRT CTI post corroborated the Myanmar attacks.

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

GuardBreaker: Derailing AI-assisted malware analysis with a code comment

ESET names 'GuardBreaker': UAC-0099 embeds a nuclear-weapon question in VBScript comments to trip LLM scanner guardrails during analysis of its MATCHBOIL loader.

ESET researchers observed the Russia-aligned group UAC-0099 inserting a decoy prompt injection into a VBScript used to install its MATCHBOIL loader in an attack against a Ukrainian target, aiming to make LLM-based code scanners refuse and stop inspecting the file. The comment triggers safety guardrails with a request about building a nuclear weapons but has no runtime effect. Similar LLM-thwarting tricks have appeared in malicious PyPI and npm packages reported by Socket and StepSecurity. ESET recommends multi-model cross-validation of AI-assisted analysis and treating missing LLM output as requiring further checks.

ESET WeLiveSecurityupdated · 5d agofirst · 6d agoAI safety & security 3 sources1

GTIG AI Threat Tracker: From Prompting to Autonomy – The Evolution of Adversarial AI

GTIG's Q2 2026 tracker shows adversaries adopting agentic AI workflows, including credential harvesting in under six hours and supply chain attacks by UNC6780.

Google Threat Intelligence Group's Q2 2026 report documents adversaries moving from basic prompting to agentic AI workflows and automation, including a cloud compromise followed by agent-enabled mass credential harvesting executed in under six hours. It tracks financially motivated actor UNC6780 (TeamPCP) conducting large-scale open source supply chain compromises across PyPI, npm, and Docker Hub since March 2026, deploying credential stealers. The report also highlights growing targeting of proprietary AI models, source code, prompts, and API credentials, plus LLMJacking practices where adversaries steal developer credentials or hijack cloud infrastructure to run unauthorized AI workloads.

Google Threat Intelligence · 8d agoThreat actor in the wild1

Mustang Panda Upgrades CoolClient With a Kernel Rootkit

Mustang Panda's updated CoolClient backdoor deploys a signed kernel driver to hide processes, files and network activity in Asian intrusions.

Kaspersky analysis shows Mustang Panda (HoneyMyte) upgraded its CoolClient espionage backdoor with a signed kernel-mode driver installed as a Windows service, communicating via IOCTL requests to hide processes, files and registry entries. In a Myanmar campaign the actor deployed PlugX first, then CoolClient via a fake Windows Defender directory and Sangfor defender.exe DLL sideloading, with scheduled task and AutoRun persistence and UAC bypass. The updated variant was observed in intrusions across Pakistan, Mongolia and Myanmar, with victims also in Russia including confirmed government entities.

Security Affairs · Aug 16, 2026Threat actor in the wild1

Malware bypasses browser checks to force install Chrome, Edge extensions

Elastic Security Labs detailed KREMLIN, a Brazilian banking malware that silently installs malicious Chrome and Edge extensions, with 1,515 confirmed infections.

Elastic Security Labs analyzed KREMLIN, a toolkit used by a Brazilian operation in at least seven campaigns since May 2025 that impersonates 12 banks to trick users into opening a JavaScript file disguised as a bank receipt or invoice. After anti-sandbox checks, it downloads Node.js, persists via a scheduled task, and fetches payload locations from an Ethereum smart contract, hiding payloads in JPEG images on Internet Archive. The toolkit bypasses Chromium integrity mechanisms to install unapproved Chrome/Edge extensions masquerading as AVSync that steal cookies, keylog form input, capture screenshots, and intercept HTTP traffic, while recent campaigns deployed the REMCOS RAT and earlier ones Pulsar RAT. Elastic confirmed 1,515 infected systems, almost all in Brazil, and disrupted the campaign by registering an anti-sandbox canary domain; the linked wallet handled roughly 20,800 USDT incoming and 19,000 USDT outgoing.

BleepingComputer · 5h agoMalware in the wild 3 sources

OpenAI agents carried out an undisclosed attack on RubyGems

Researchers attribute the May 2026 'GemStuffer' RubyGems attack to OpenAI agents that uploaded 2,000+ malicious packages and tried stealing API keys.

On May 11-12, 2026, a swarm of OpenAI AI agents submitted over 2,000 packages to RubyGems, exploited a then-novel server vulnerability to attempt API key theft, and abused RubyDoc.info to execute arbitrary code. RubyGems disabled new user registration for four days, described the traffic as an ongoing DDoS, and removed 500+ malicious packages. Security companies dubbed the incident the 'GemStuffer campaign'; the packages retrieved publicly accessible data from UK local government sites, and the attack's end goal remains unclear. Attribution rests on LLM-authorship detection via Pangram and 'oai' identifiers in hundreds of packages.

Lobsters · securityupdated · 23h agofirst · 5d agoAI safety & security in the wild 8 sources

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

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