ZeroHour
DashboardNewsCVEsExploitsIncidentsAIBriefAnalyticsEntitiesWatchlistIOCsAsk the feedSourcesFeeds & APIKiosk mode

Search: “Windows Defender”

167 stories

Searchkeywordsmart Sortlatesthotimportancerelevance
DomainAllCyberAIWindow24h3d7d30dAllIn the wildImportant onlyShow duplicates
CategoryAllMalware 669Ransomware 631Vulnerability 553Exploit / PoC 261Threat actor 173Data breach 106Policy & legal 77Industry 67Phishing & fraud 60AI safety & security 23Advisory 20Research 18AI industry 9Tools 8
SeverityAllcritical 1128high 847medium 535low 98info 78

Threat Brief: Ongoing Russia and Ukraine Cyber Activity

Ukrainian government sites were defaced via OctoberCMS CVE-2021-32648 while Microsoft-attributed actor DEV-0586 deployed destructive WhisperGate malware.

Unit 42 tracks January 2022 attacks against Ukrainian government websites that were defaced or made inaccessible, which Ukraine attributed to Russia. Attackers exploited CVE-2021-32648, an account takeover flaw in OctoberCMS prior to 1.0.472, by submitting a boolean true as the password reset code to bypass validation. Separately, WhisperGate malware, attributed by Microsoft to DEV-0586, disabled Windows Defender and corrupted files across multiple Ukrainian organizations, using a ransomware-appearing first stage and an HTTPS-beaconing second stage with LOLBINs and anti-analysis techniques.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wildCVE-2021-326481

Aggah Campaign: Bit.ly, BlogSpot, and Pastebin Used for C2 in Large Scale Campaign

Aggah campaign abuses Bit.ly, BlogSpot, and Pastebin as multi-hop C2 to deliver RevengeRAT across the Middle East, US, Europe, and Asia.

Unit 42 details the Aggah campaign, which began with spearphishing emails in March 2019 spoofing a large financial institution and targeting education, media/marketing, and government organizations in the Middle East, later expanding to the US, Europe, and Asia. Delivery documents use Template Injection to load a remote OLE file whose macro runs mshta against a Bit.ly link redirecting to a BlogSpot post, which then uses Pastebin pastes to download RevengeRAT configured with a duckdns[.]org C2 domain. The embedded script also deletes Microsoft Defender signatures and kills Defender and Office processes, and modifies registry keys to enable macros. High-level TTPs resemble the Gorgon Group, but Unit 42 could not confirm attribution.

Palo Alto Unit 42 · Aug 17, 2026Threat actor

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

Counterfeit installers to system compromise: Tracking a deceptive software download campaign

Microsoft tracks a counterfeit software-installer campaign compromising multinationals' China operations, moderately linked to the Silver Fox (Yinhu) actor.

Microsoft Defender Experts is tracking an active campaign using spoofed software download sites for brands such as Razer, Kaspersky, Microsoft Edge, Calibre, and Baidu Netdisk on .com.cn and .hl.cn domains, delivering installer archives whose hashes change per download, indicating server-side payload generation. The implants establish persistence, weaken security protections, and communicate with attacker-controlled infrastructure, with confirmed compromises across healthcare, manufacturing, gaming, technology, logistics, government, and education. Microsoft assesses with moderate confidence that the activity matches the publicly reported Silver Fox (Yinhu) fake software campaign; it has not attributed it to a nation-state actor.

Microsoft Security Blog · 14d agoThreat actor in the wild1

ThreatsDay: CEO Phishing Kits, 5K Dropbox Account Hacks, OAuth Traps + 17 More Stories

Microsoft warns of Teams IT-impersonation intrusions deploying Node.js implants; Spring Ring vishing hit 150+ employees across 10 companies; The Gentlemen ransomware claims 683 victims.

Microsoft warned of a human-operated campaign abusing Teams external collaboration to impersonate IT help desk staff, deploy malicious MSI packages staging Node.js runtimes and obfuscated JavaScript implants, then pivot to domain controllers over WinRM. Unit 42 documented the Spring Ring vishing operation targeting over 150 employees across at least 10 companies using 26 attacker identities, including an NTLM relay variant against domain controllers. Sophos reported The Gentlemen ransomware (Gold Sherwood) reached 683 total victims by end of July 2026, adding 169 in July, with a playbook using BYOVD-based EDR killers and backup tampering. Group-IB found the Outsider phishing-as-a-service platform created 700+ new phishing pages within a month despite law enforcement takedowns.

The Hacker News · 13d agoThreat actor in the wild1

Mustang Panda Adds Signed Windows Rootkit to CoolClient Backdoor for Stealth

Kaspersky reports Mustang Panda's updated CoolClient backdoor now deploys a signed kernel-mode Windows rootkit, hitting government victims in Myanmar, Mongolia, Pakistan, and Russia.

Kaspersky identified a new CoolClient variant attributed to HoneyMyte (Mustang Panda) that installs a digitally signed Windows kernel driver, msagent.sys, to hide and protect malicious processes, files, registry keys, and C2 network information. CoolClient is consistently deployed as a secondary backdoor after PlugX, with confirmed victims including government entities in Myanmar, Mongolia, Pakistan, and Russia. In a Myanmar campaign, PlugX was used to deploy CoolClient via a renamed Sangfor executable for DLL side-loading, a scheduled task for persistence, and RPC-based process creation with PPID spoofing. The driver, signed with a 2013 certificate issued to Nanjing Ranyi Technology, implements 33 IOCTL handlers, process hiding via unlinking, a filesystem minifilter, and registry callbacks.

The Hacker News · Aug 15, 2026Threat actor in the wild1

Inside Operation CameraSwarm: How One Actor Took Over 14,000 Dahua Cameras

One actor compromised over 14,000 Dahua cameras in Ukraine and Russia using brute-force, authentication bypass, and cloud relay serial-number abuse.

Hunt.io reconstructed Operation CameraSwarm from an exposed operator directory, revealing one actor compromised 14,000+ Dahua cameras between June 17 and July 22, 2026, mainly in Ukraine and Russia. The toolkit included a brute-force engine, a two-flaw 2021 authentication-bypass chain planting a persistent backdoor account on 1,923 cameras, and abuse of Dahua's cloud relay where 89.4% of probed serials returned open, unauthenticated channels. A SalatStealer Windows binary and Defender-disabling PowerShell script were staged on the same server but appear unrelated to the camera campaign.

Security Affairs · 28d agoThreat actor in the wildCVE-2024-39943CVE-2025-31702

Iranian cyber targeting of dissidents, activists and journalists

UK NCSC, FBI, and Dutch AIVD expose CHOSEN BRICK spyware used by Iranian state actors against dissidents, activists, and journalists worldwide.

A joint advisory from the UK NCSC, FBI, and Dutch AIVD details CHOSEN BRICK, a Windows spyware family used by Iranian state cyber actors since at least 2025 against dissidents, activists, and journalists in the UK, US, and Netherlands. Actors build rapport on WhatsApp and Telegram impersonating known contacts or platform support, then deliver disguised payloads resembling apps such as Telegram, Norton, RunwayML, or fake MRI results. The malware persists via HKCU Run registry keys, adds Microsoft Defender exclusions, and uses a unique Telegram bot C2 per victim. Capabilities include screen capture, microphone recording, process enumeration, email and messaging data theft, file deletion, and system wiping; victim data has appeared on pro-Iranian leak sites.

NCSC UK · 1d agoThreat actor in the wild2

ThreatsDay: Gogs 10.0 RCE, n8n Workflow-to-RCE, $10M Reward, GLM

Hacker News ThreatsDay roundup: Defender BTR.sys driver abuse, DoJ charges 17 Mabna Institute members over IRGC-linked intrusions, Grandoreiro sideloading, OpenAI monitoring.

Check Point researchers showed Microsoft's signed Defender Boot-Time Removal driver (BTR.sys) can be repurposed as a universal kernel operation engine to bypass endpoint security without BYOVD. The DoJ charged 17 members of Iran's Mabna Institute, which on behalf of the IRGC stole over 31 TB of academic data from 144 US universities and compromised roughly 8,000 of 100,000 targeted professor accounts; the State Department offered a $10 million reward for five defendants. Separately, Acronis tracked a Grandoreiro campaign abusing DLL sideloading in the Duplicate Files Finder app across Latin America and Spain, while ErrTraffic ClickFix campaigns deliver Cruciferra (BYOVD) and Remus Stealer. OpenAI also previewed Private Safety Processing, a privacy-centric approach to monitoring model misuse without retaining customer content.

The Hacker News · 26d agoThreat actor1

The Top 4 Threats We Found by Investigating Every Alert for a Quarter

Prophet Security's quarterly threat report finds identity attacks made up roughly half of confirmed malicious activity, with stolen authenticated sessions bypassing conditional access controls.

Between May 1 and July 31, 2026, Prophet Security investigated every alert in customer environments immediately on arrival; about 7% of completed investigations were confirmed malicious. Direct account/session attacks made up roughly 18% of confirmed activity, with replayed authenticated sessions bypassing conditional access since no re-authentication occurs. Infostealer activity affected about a quarter of investigated organizations, mostly delivered via browsers through compromised websites, malicious ads, sponsored search results and ClickFix fake CAPTCHA gates, with payloads including Lumma Stealer, Vidar, HijackLoader and AsyncRAT. Credential phishing was the largest category at about 28%, with adversary-in-the-middle relays revealed by seconds-long MFA approvals from distant countries and MFA fatigue attacks exploiting automatic unlock policies.

BleepingComputer · 6d agoThreat actor in the wild

Breeze Comet Executes Hundreds of Fraudulent Transactions via Brazilian Payment Systems

Google/Mandiant profile Breeze Comet, a Brazil-based e-crime group executing fraudulent Pix and STR payment transactions at banks, retailers, and fintechs.

Google Threat Intelligence Group and Mandiant describe Breeze Comet (formerly UNC5669), a financially motivated threat actor active since September 2023 targeting Brazilian financial services, retail, and e-commerce. The group gains access via password spraying, vishing impersonating IT support to install RMM tools like AnyDesk, WhatsApp social engineering, and exploitation of vulnerable JBoss AS servers for web shell deployment. It uses compromised government websites as C2, deploys the Rust-based COBALTSPIN tunneler and multiple custom backdoors (LIGHTPAINT, MILDFROST, KICKPLATE, BOATBEAM), then clears logs after executing hundreds of fraudulent transactions through Pix, STR, and Boleto payment systems. At least one heist yielded tens of thousands of dollars, with infrastructure suggesting expansion toward Latin America and Africa.

The Hacker News · 8d agoThreat actor in the wild

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

Hackers Use Autonomous AI Agents to Harvest Thousands of Credentials in Under 6 Hours

Google Cloud documents a financially motivated actor using autonomous AI agents on a compromised cloud tenant to harvest 23,800+ credentials in under six hours.

Google Cloud reports that an attacker compromised a victim's cloud environment and deployed a multi-agent framework driven by preconfigured Markdown playbooks to autonomously handle vulnerability scanning, credential collection, error troubleshooting, and IP rotation. An exposed command-and-control server hosted the 'Recon' framework with a live dashboard managing over 23,800 harvested secrets, including cloud and AI-service API keys. The report also ties DUSTMAKER to UNC6780/TeamPCP, targeting AI development tools and CI/CD systems via trojanized MCP packages such as tiktoken_mcp. Google has disabled linked assets and updated protections after the actors' operational security failures.

Cyber Security News · 1d agoThreat actor in the wild

Hackers build AI frameworks for widescale credential theft

Google GTIG details threat actors using autonomous multi-agent AI frameworks to automate attacks, including a six-hour credential-harvesting campaign and a 23,800-secret Recon panel.

Google Threat Intelligence Group (GTIG), drawing on Mandiant telemetry, reports threat actors are moving from AI coding assistants to autonomous multi-agent frameworks that automate vulnerability scanning, credential harvesting, troubleshooting, and IP rotation. In one incident, a financially motivated attacker compromised cloud infrastructure and deployed such a framework, harvesting thousands of third-party credentials in under six hours. An exposed C2 server hosted the 'Recon' framework, managing over 23,800 harvested secrets including API keys, with OpenClaw artifacts. GTIG also documents China-linked espionage actors building AI-assisted exploitation pipelines and Russia-based UNC5792 automating Telegram monitoring, while noting fully autonomous zero-day discovery is not yet widespread.

BleepingComputer · 8d agoThreat actor1

Counterfeit installers turn routine software downloads into enterprise breaches

Microsoft warns of a multi-sector campaign using counterfeit download sites for Edge, Kaspersky and Razer to deliver trojanized installers with persistent implants.

Microsoft Defender Experts tracked a campaign breaching organizations in healthcare, manufacturing, gaming, technology, logistics, government, and education via spoofed vendor download pages, often using .com.cn and .hl.cn domains. Installers keep the same filename while their hash changes on every download, indicating server-side payload generation that defeats file-based detection. The chain abuses msiexec.exe and scheduled tasks for persistence, adds Defender exclusions, deletes shadow copies, and disables Windows Update, with some hands-on-keyboard activity. The activity is consistent with the publicly reported Silver Fox (Yinhu) campaign, though Microsoft has not attributed it to a nation-state actor.

CSO Online · 13d agoThreat actor in the wild1