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CDN Tsunami Attack Abuses HTTP/3 Translation for Up to 350x DoS Amplification

Researchers disclosed two DoS attacks exploiting CDNs' HTTP/3-to-HTTP/1.1 translation to amplify low-bandwidth requests up to 350x against origin servers.

Researchers named the two techniques HTTP/3 Bandwidth Amplification (HBA) and HTTP/3 Connection Amplification (HCA), exploiting the gap where CDNs speak HTTP/3 to browsers but only HTTP/1.1 to origins. All six tested CDNs (Alibaba, Baidu, Cloudflare, CloudFront, Fastly, Tencent) were susceptible to HBA, and five to HCA, with Cloudflare immune to HCA because it buffers full requests before opening backend connections. Attackers using under 5 Mbps forced over 100 Mbps at origins, and the 350x factor applies only to Alibaba, Baidu, and Tencent, which support the QPACK dynamic table. Testing identified 42,330 potentially vulnerable subdomains out of 151,685 hosted on the six providers across the Tranco Top 1M.

The Hacker News · 27d agoResearch

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

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

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

Iran-linked APT Mirage Kitten Uses Fake Job Tests to Spread Malware

Kaspersky reports Iran-linked Mirage Kitten delivers new NodeRabbit and PollCat malware to fintech and aviation targets via fake LinkedIn coding assessments.

Kaspersky researchers documented two previously undocumented Node.js malware families, NodeRabbit and PollCat, attributed with high confidence to Iran-linked APT group Mirage Kitten. The malware is delivered via fake recruiter personas on LinkedIn offering coding assessments hosted on Amazon S3, with instructions banning AI assistants so AI code-review tools would not flag the trojanized npm packages. NodeRabbit is cross-platform (Windows, Linux, macOS), uses AES-256-GCM-encrypted C2 on Azure, includes sandbox checks, and one variant installs a fake 'GitHub Copilot Helper' VS Code extension plus Git hook persistence. Victims identified so far are in fintech and aviation organizations across Egypt, Ethiopia, and Afghanistan.

Security Affairs · 14d agoThreat actor in the wild2

The Coding-Agent Trap: When a "Free" LLM Endpoint Is the Adversary, (Mon, Aug 31st)

A SANS honeypot caught a real coding-agent session routed to a rogue "free" LLM endpoint, exposing a Windows user's transcript and tool outputs.

A SANS analyst describes how an internet-exposed inference honeypot was discovered, relabeled with sought-after model names like DeepSeek, and enrolled in infrastructure serving "free" LLM backends. On 2026-08-30 an opencode terminal coding agent sent an 88-message, 224 KB transcript 210 times in 91 seconds via a China Unicom relay, exposing directory listings, tool outputs and read file portions. The analyst frames tool-enabled agents treating model endpoints as trusted control planes as a novel risk — a "rogue model endpoint" that could request tool executions on the user's machine.

SANS Internet Storm Center · 16d agoAI safety & security1

Storm-1175 Replaces Medusa With New StormEncryptor Ransomware

Microsoft reports China-linked ransomware group Storm-1175 switched from Medusa to a new C++ strain, StormEncryptor, likely exploiting N-able flaw CVE-2026-18577.

Microsoft Threat Intelligence reports that the financially motivated, China-linked group Storm-1175 began deploying a new ransomware strain called StormEncryptor on August 2, 2026, replacing its previous Medusa ransomware. StormEncryptor is written in C++, appends the .encrypted extension to files, and drops a !!!README_FIRST!!!.txt ransom note in each scanned directory. Microsoft assesses the group is likely exploiting CVE-2026-18577, an authentication bypass in N-able disclosed on August 2, 2026 and added to CISA's Known Exploited Vulnerabilities catalog the next day. Since 2023, Storm-1175 has exploited more than 16 vulnerabilities in products including Microsoft Exchange, Ivanti, ConnectWise ScreenConnect, JetBrains TeamCity, SimpleHelp, CrushFTP, and GoAnywhere MFT, often moving from initial access to data theft and ransomware deployment within days.

Security Affairs · Aug 13, 2026Ransomware in the wildCVE-2026-18577CVE-2026-1731CVE-2023-21529+15 CVEs1

737 Chrome VPN Extensions Caught Routing Traffic Through Proxies. Check If You Have One

Researchers found 737 Chrome VPN extensions, many impersonating brands like NordVPN, routing roughly 75,000 users' browser traffic through attacker-controlled SOCKS5 proxies.

Socket and researcher Kush Pandya identified 737 Chrome VPN and proxy extensions, published across at least 40 developer accounts with 75,486 installs, that route entire browser sessions through one provider's SOCKS5 proxies on port 1082. Of these, 274 impersonate 66 established brands including Proton VPN, NordVPN, Surfshark, ExpressVPN, and Cloudflare 1.1.1.1. The proxy bypass list only excludes loopback addresses, exposing visited destinations, source IPs, TLS SNI values, and plain-HTTP request bodies to the operator. 221 extensions have been removed from the Chrome Web Store while 516 remain listed as active.

The Hacker News · Aug 12, 2026Malware