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Cloudflare Workers Spectre Attack Leaks JWT From Co

Researchers demonstrated a remote Spectre attack leaking a JWT between co-located Cloudflare Workers at 12 bits per second, 360x the 2021 rate.

Security researchers showed a remote Spectre attack against Cloudflare Workers that leaked a JWT from a co-located Worker at up to 12 bits per second with 99.16% accuracy, 360 times the 2021 demonstration rate. The attack exploited weaknesses in DyPrIs dynamic process isolation, where long-lived Durable Object invocations could run before isolation and WebSocket-heavy I/O suppressed the branch-misprediction signal. Cloudflare deployed improved DyPrIs, the V8 Sandbox, and MPK-based in-process isolation, and found no indicators of active exploitation over three years.

The Hacker News · 28d agoVulnerability

ClearFake WebDAV infection chain delivers Amatera stealer, ZigCryptoStealer, and NetSupport Manager

Cisco Talos details ClearFake WebDAV chains delivering Amatera stealer to a Ukrainian government organization, with cryptocurrency and credential theft payloads.

Cisco Talos investigated DLL executions named 'verification.google' via WebDAV UNC paths at a Ukrainian government organization, tracking the actor as UAT-10820 and assessing with moderate confidence the activity is Russian and opportunistic rather than targeted. The infection chain uses ClearFake JavaScript injected via a Cloudflare Worker, EtherHiding storage on BNB Smart Chain contracts, and a ClickFix fake Google CAPTCHA prompt to deliver Amatera stealer. Secondary payloads differ by C2: one loader deploys ZigCryptoStealer with a Go reverse TCP proxy and a vulnerable driver that kills EDR, while the other installs an unauthorized NetSupport Manager with a Russia-based C2. Similar Amatera chains were separately documented by Malwarebytes and Blackpoint Cyber, but with no shared infrastructure.

Cisco Talos · 8d agoMalware in the wild1

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

Hackers Abuse Google CAPTCHA, WebDAV and BNB Smart Chain to Deploy Credential-Stealing Malware

Cisco Talos details ClickFix campaigns abusing fake Google CAPTCHA prompts, WebDAV and BNB Smart Chain to deploy the Amatera infostealer.

Cisco Talos identified a multi-stage campaign, first observed in April 2026 when a Ukrainian government organization executed a disguised DLL named verification.google from a WebDAV path. The chain combines ClearFake JavaScript injected via malicious Cloudflare Workers, EtherHiding payloads stored in BNB Smart Chain contracts, ClickFix social engineering, and WebDAV-hosted DLL loaders to deliver the Amatera (ACR Stealer) infostealer. The Amatera configuration contained over 400 collection entries targeting browsers, messengers, crypto wallets, password managers, FTP and VPN tools, hunting for .kdbx, .p12, .pfx and .pem files. The pf.ch branch deploys ZigCryptoStealer, an EDR-terminating vulnerable driver and Go-based reverse TCP proxies, while the verification.google branch installs NetSupport Manager, supporting moderate-confidence attribution of the UAT-10820 activity to a Russian actor.

GBHackers · 7d agoMalware in the wild

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

E4del and PINHOLE RATs Turn FTP Banners Into Dead Drops for Malware Commands

Researchers identified two new RATs, E4del and PINHOLE, using FTP banners as dead drop resolvers to fetch C2 commands via ClickFix-style lures.

SOCRADAR documented two previously unreported RATs, E4del and PINHOLE, that use FTP banners as dead drop resolvers, a first in-the-wild use of this technique. E4del is a Node.js-based RAT hidden in a digitally signed Electron application masquerading as Discord, with tiered-jitter beaconing, reverse shell, screenshot capture and desktop streaming. PINHOLE is more advanced, using Pinterest, SurveyMonkey and Cloudflare Workers for C2 resolution, six layers of unpacking, Halo's Gate EDR evasion and Early Bird APC injection. A related WebDAV delivery chain overlaps with ClearFake campaigns distributing WordlistLoader and Amatera Stealer.

The Hacker News · 22d agoMalware in the wild

40 Malicious Firefox Extensions Pose as Web3 Products to Steal Wallet Secrets

Socket found 40 malicious Firefox extensions impersonating OKX, Rabby Wallet, and TronLink to steal cryptocurrency wallet recovery phrases and private keys.

The Socket Threat Research team identified 40 malicious Firefox extensions masquerading as Web3 products including OKX, Rabby Wallet, and TronLink, part of a broader set of 77 add-ons sharing source code and infrastructure overlaps. The campaign, dubbed Offside Wallet Theft Factory, has been active since March 2026 and remains unattributed. Of the 40 confirmed malicious extensions, 15 capture recovery phrases and private keys exfiltrated through Cloudflare Workers, 13 modified Rabby Wallet builds exfiltrate serialized keyrings before local encryption, seven use attacker-controlled Supabase projects as remote switches, and five capture credentials and clipboard data via hard-coded C2. Some extensions began as sports score or utility shells before being repurposed into wallet stealers under the same Firefox ID.

The Hacker News · 27d agoMalware 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

Autonomous AI Agents Compromise Thousands of Credentials in Under Six Hours

Google's GTIG reports threat actors using autonomous AI agents, credential stealers, and LLMs to steal AI models, API credentials, and harvest thousands of credentials.

Google Threat Intelligence Group says attackers are targeting proprietary AI models across healthcare, government, and media, exfiltrating API credentials, and co-opting victim cloud environments to run unauthorized AI workloads. TeamPCP (Altered Spider/UNC6780) is conducting supply chain compromises of PyPI, npm, and Docker Hub, deploying the SANDCLOCK and DUSTMAKER credential stealers, with DUSTMAKER using AI workspace poisoning and prompt injection for defense evasion. One financially motivated actor used an autonomous multi-agent framework to compromise thousands of third-party credentials in under six hours without human intervention. China-nexus groups UNC6508 and Basin Castle (Mustang Panda) used local open-weight LLMs and commercial LLMs like Gemini, Claude, and Codex for espionage tasks and evading provider monitoring.

The Hacker News · 8d agoThreat actor in the wild 2 sources1

Hackers Use ClickFix Lures to Deploy MacSync Stealer and Bypass macOS Security.

ClickFix malvertising campaigns deliver MacSync, a macOS infostealer sold as MaaS that bypasses Gatekeeper via Terminal commands and steals credentials.

Threat actors use ClickFix social-engineering lures, SEO poisoning, and malvertising impersonating brands like Claude, ChatGPT, Zoom, and Docker to trick users into pasting curl-to-zsh commands into Terminal, evading Gatekeeper and notarization checks. The MacSync Stealer (formerly Mac.c, emerged April 2025, linked to developer 'Mentalpositive') is a 64-bit Mach-O stager with single-byte XOR string obfuscation that daemonizes, polls C2 with custom API-key headers, streams AppleScript payloads into osascript, and persists via fake LaunchAgents. It steals browser credentials, Keychain data, SSH keys, session tokens, and crypto wallets, exfiltrating archives in 10MB HTTP PUT chunks. Microsoft documented more than 30 related MacSync domains.

GBHackersupdated · 6d agofirst · 6d agoMalware in the wild 2 sources

TuxBot v3: Inside an IoT Botnet Framework With LLM

Unit 42 uncovers TuxBot v3, an LLM-assisted IoT botnet framework with 17-architecture builds, Telnet brute-forcing, and DDoS capabilities.

Palo Alto Unit 42 identified TuxBot v3 Evolution, a modular IoT botnet framework derived from AISURU, Wuhan-lineage botnets, and MHDDoS. The C-based bot brute-forces Telnet with 1,496 credential pairs, targets over 30 IoT device families, and communicates with a Go-based C2 over encrypted TCP with multiple fallback mechanisms including DGA, P2P, and DNS TXT. LLM-assisted development left hallucinated crypto implementations and broken exploit modules in the analyzed samples, though roughly 70% of core functionality works. Researchers warn polished production builds likely exist, raising the threat potential.

Palo Alto Unit 42 · 28d agoMalware1