ZeroHour
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Microsoft Defender

16 mentions in 7 days · 28 in 30 days · 33 total · first seen · last

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Researchers Uncover 10,000+ Malware Loaders Behind YouTube and SEO Poisoning Campaign

Unit 42 uncovers CL-CRI-1171, a two-year pay-per-install campaign distributing 10,000+ OfferLoader samples via YouTube and SEO poisoning.

Palo Alto Networks Unit 42 tracked a campaign as CL-CRI-1171, an infection-as-a-service platform operating for at least two years. It used 11 YouTube gaming channels with hundreds of thousands of subscribers and SEO-poisoned download pages for trojanized WinDirStat and Bluetooth driver installers to distribute OfferLoader, a disposable loader embedded in Inno Setup installers. Payloads delivered included Insomnia RAT (Node.js and Python backdoors), ARKTunnel (a WebSocket-based RAT using LSB steganography), and Docro Hijacker (Chrome browser hijacker), with later infections delivering GCleaner and Socks5Systemz. Over 200 rotating domains across .xyz, .cfd, .space, and .info TLDs were used, with gating filters that served broken links or decoy pages to scanners and researchers.

GBHackers · 4d agoMalware in the wild 2 sources2

Hackers Use AI-Assisted CEO Emails to Trick Finance Teams Into Sending $50,000 Payments.

Microsoft tracked a million-message AI-assisted BEC campaign impersonating executives with fake ServiceNow invoices to steal ~$50,000 ACH payments.

Microsoft detected over one million messages in a BEC campaign running August 3-5, using AI-assisted phishing templates, executive impersonation, and fabricated ServiceNow subscription invoices to trick finance teams into authorizing fraudulent ACH payments of roughly $50,000. The US received 87.7% of volume. Attackers used lookalike domains like service-nowinc[.]com registered just days before delivery, with no compromise of ServiceNow itself. Telltale signs included verbose HTML comments, uniform formatting, and inconsistent forwarded-message headers.

GBHackersupdated · 4d agofirst · 4d agoPhishing & fraud in the wild 2 sources

Hackers Deploy New SloppyRAT via ClickFix to Enable Ransomware Lateral Movement

Zscaler ThreatLabz reports SloppyRAT, a new Windows RAT delivered via ClickFix lures that supports reconnaissance, reverse SOCKS proxying, and lateral movement for ransomware affiliates.

Zscaler ThreatLabz first observed SloppyRAT in June 2026, delivered through multi-stage ClickFix chains that abuse finger.exe, a renamed curl.exe, and IronPython to load a reflective Python payload. The C++ implant implements 47 PowerShell-like commands via native APIs and direct syscalls, modifies Microsoft Defender settings, and establishes a reverse SOCKS proxy that lets operators pivot into internal networks. It is linked to CastleLoader and CastleRAT components and uses certificate-pinned HTTPS C2 with an EtherHiding fallback via Polygon JSON-RPC. Zscaler assesses it as an intrusion-enablement tool for ransomware operations, though flawed persistence logic suggests the family is still under development.

GBHackersupdated · 4d agofirst · 4d agoMalware in the wild 3 sources

We've got one word for it, and it's usually the wrong one

Cisco Talos's Threat Source newsletter critiques 'burnout' terminology, describing four occupational injuries, and flags a UAT-10820 WebDAV stealer campaign at a Ukrainian government organization.

Cisco Talos's Threat Source newsletter argues that 'burnout' is the wrong word for most cybersecurity occupational harm, distinguishing exhaustion, secondary traumatic stress, vicarious trauma, and moral injury based on clinical literature from trauma-exposed professions. The featured disclosure describes a complex WebDAV infection chain found at a Ukrainian government organization, attributed with moderate confidence to the Russian-tracked actor UAT-10820 and assessed as an opportunistic cryptocurrency and credential-stealing operation. The campaign delivers the Amatera stealer alongside ZigCryptoStealer and NetSupport Manager, abusing BNB Smart Chain bulletproof hosting, fake CAPTCHA prompts, a vulnerable driver to kill EDR, and rundll32.exe execution of disguised DLLs with ordinal calls. Weekly headlines also cover a Microsoft Defender 'ShieldCrash' zero-day exploit released after September 2026 Patch Tuesday, a North Korean Linux espionage toolkit backdooring HAProxy, and a multi-hop Google-domain redirect phishing campaign.

Cisco Talosupdated · 4d agofirst · 5d agoIndustry in the wild 4 sources1

Detect and disrupt AI-themed attacks with Microsoft Defender

Microsoft Threat Intelligence reports criminal campaigns impersonating ChatGPT, Copilot, Claude, and DeepSeek in phishing, AiTM, and malvertising attacks reaching 100,000 emails daily.

Microsoft Threat Intelligence observed a growing set of campaigns that abuse trust in popular AI brands: a ChatGPT-themed phishing campaign sent up to 100,000 emails in one day to steal payment card data, and a Claude-themed campaign used adversary-in-the-middle techniques to harvest credentials and access tokens. Other campaigns included malvertising for a fake AI Windows plugin delivering the Vidar stealer and fraudulent DeepSeek installers distributed via GitHub. Initial access broker Storm-3075 used AI-themed malvertising to distribute payloads for multiple downstream actors, and Microsoft notes the AI services themselves were not compromised. Microsoft also details Defender protections such as Safe Links, Safe Attachments, and attack disruption against these multi-stage lures.

Microsoft Security Blog · 5d agoPhishing & fraud in the wild1

ShieldCrash PoC: Microsoft Defender Fix Bypass

A ShieldCrash proof-of-concept bypasses Microsoft's patch for CVE-2026-69414, a high-severity elevation-of-privilege flaw in the Microsoft Malware Protection Engine.

Microsoft previously fixed CVE-2026-69414 (ShieldBreak), a high-severity elevation-of-privilege vulnerability in the Microsoft Malware Protection Engine used by Microsoft Defender. SOCRadar now reports a new proof-of-concept dubbed ShieldCrash demonstrating that the published fix can be bypassed. The available source text does not detail affected versions or whether the bypass has been used in real attacks.

Top 10 Best Ransomware Protection Solutions in 2026

A 2026 buyer's guide ranks ten ransomware protection tools by kill-chain role as extortion shifts from encryption to data theft.

The roundup organizes defenses across the ransomware kill chain: prevention-grade EPP/EDR platforms, containment layers, rollback specialists, and immutable recovery. Recommended products include CrowdStrike, Microsoft Defender, Sophos, SentinelOne, Bitdefender, Trend Micro, Halcyon, Huntress, and Malwarebytes. It stresses that many crews now extort on stolen data without encrypting, making exfiltration detection and response speed as important as rollback.

Cyber Security News · 5d agoIndustry1

New ‘ShieldCrash’ Zero-Day Exploit Targets Microsoft Defender

Researcher Nightmare Eclipse released ShieldCrash, a Microsoft Defender zero-day PoC bypassing ShieldBreak patches to gain System privileges on Windows.

The researcher known as Nightmare Eclipse released a PoC zero-day exploit dubbed ShieldCrash against Microsoft Defender on fully patched Windows systems. The exploit grants arbitrary file read with System privileges and can be used to drop the SAM database. It bypasses Microsoft's September 3 fixes for ShieldBreak (CVE-2026-69414), which itself bypassed patches for the RoguePlanet race condition (CVE-2026-50656). Microsoft has been contacted for comment and has not yet responded.

SecurityWeekupdated · 5d agofirst · 5d agoExploit / PoC 8 sourcesCVE-2026-50656CVE-2026-694141

Serial Microsoft 0-day hunter drops yet another Defender exploit

Researcher Nightmare Eclipse released ShieldCrash, a Microsoft Defender zero-day PoC that bypasses September patches and reads files as SYSTEM.

Zero-day researcher Nightmare Eclipse (MSNightmare) published ShieldCrash, their 11th Microsoft zero-day, a proof-of-concept bypass of the ShieldBreak patch (CVE-2026-69414), which itself had bypassed the fix for RoguePlanet (CVE-2026-50656). ShieldCrash works on Windows 10, Windows 11, and Windows Server systems that have applied the September 2026 patches and allows arbitrary file reads as SYSTEM, though not arbitrary writes or a full SYSTEM shell. Microsoft has not said when it plans to patch the issue. The researcher recently also released zero-days affecting CrowdStrike Falcon (FalconFlank), Kaspersky endpoint antivirus (HardBreacher, patched), and Gen Digital's Avast (PrettyPrague).

The Register · Securityupdated · 5d agofirst · 6d agoExploit / PoC 8 sourcesCVE-2026-69414CVE-2026-50656

New Windows Defender ShieldCrash 0-Day Bypasses Microsoft Patch to Read Files as SYSTEM

Researcher's ShieldCrash PoC claims Microsoft Defender still allows arbitrary file reads as SYSTEM on patched Windows, bypassing the CVE-2026-69414 fix.

Researcher MSNightmare released the ShieldCrash proof of concept showing Microsoft Defender can allegedly be made to read arbitrary files with SYSTEM privileges on fully patched Windows systems, bypassing the September 2026 fix for ShieldBreak (CVE-2026-69414). Microsoft has not confirmed the bypass, and the new flaw has no CVE assignment yet. The PoC repository contains C++ project files, a Warden.dll library, and an EICAR test archive, suggesting interaction with Defender's malware-detection and file-handling workflow. Reading files as SYSTEM could expose configuration files, credentials, private keys, and other users' data, though it does not enable code execution.

Cyber Security Newsupdated · 5d agofirst · 6d agoVulnerability 8 sourcesCVE-2026-69414

September 2026 Patch Tuesday forecast: All we need is more time

September 2026 Patch Tuesday forecast expects record CVE volume after August's 398 fixes, with SharePoint flaws CVE-2026-55040 and CVE-2026-63520 actively exploited.

This Patch Tuesday forecast column notes August 2026 Patch Tuesday was the second largest ever with 398 resolved CVEs, yet only one was confirmed actively exploited. SharePoint flaws CVE-2026-55040 and CVE-2026-63520 are being chained for authentication bypass and remote code execution in active attacks against unpatched servers. Microsoft Defender's ShieldBreak elevation of privilege flaw (CVE-2026-69414) is publicly disclosed with PoC code and a fix is expected, while Chrome CVE-2026-85046 was reported exploited in the wild. Several products, including Windows 11 24H2 Home/Pro and Exchange Server 2016/2019 ESU, reach end of support in October 2026.

Help Net Security · 6d agoAdvisory in the wildCVE-2026-55040CVE-2026-63520CVE-2026-62911+5 CVEs1

September 2026 Patch Tuesday: Record patch count, 2 zero-days, and a SigRed successor

Microsoft's September 2026 Patch Tuesday delivers a record patch count, fixing two exploited zero-days and a wormable DNS flaw dubbed a SigRed successor.

Microsoft's September 2026 Patch Tuesday sets another record patch count, fixing two vulnerabilities exploited as zero-days: CVE-2026-81963, a Windows Update Stack low-privilege-to-SYSTEM escalation reported by MSTIC, and CVE-2026-85880, a Windows Advanced Local Procedure Call escalation reported by Proofpoint. Zero Day Initiative's Dustin Childs urges priority on a cluster of 20 potentially wormable bugs including DNS RCE CVE-2026-69730, described as a spiritual successor to SigRed, plus Kerberos authentication bypass CVE-2026-69676 that could give any authenticated domain user RCE on domain controllers, and Exchange RCE CVE-2026-55007 via a malicious Visio attachment. All Windows fixes are bundled in cumulative updates, and experts stress prioritizing exploitable, reachable flaws over raw patch counts.

Help Net Security · 6d agoAdvisory in the wildCVE-2026-81963CVE-2026-85880CVE-2026-69730+4 CVEs

Windows Defender ShieldCrash 0-Day Lets Attackers Read Arbitrary Files as SYSTEM

Unpatched Windows Defender zero-day 'ShieldCrash' PoC lets local attackers read arbitrary files as SYSTEM, apparently bypassing the CVE-2026-69414 patch.

Researcher MSNightmare published a skeleton proof-of-concept for 'ShieldCrash', an unpatched Microsoft Defender flaw enabling arbitrary file reads with SYSTEM privileges that reportedly persists on supported Windows versions after September 2026 updates. It appears to bypass the recent fix for the Malware Protection Engine elevation-of-privilege flaw CVE-2026-69414 (ShieldBreak), patched in engine version 1.1.26080.3. SYSTEM-level file disclosure could expose credentials, application secrets and registry hives and support post-compromise reconnaissance. No active exploitation is confirmed and Microsoft had issued no specific patch or mitigation at disclosure time.

GBHackersupdated · 5d agofirst · 6d agoExploit / PoC 8 sourcesCVE-2026-69414

Chaotic Eclipse Released ShieldCrash, A PoC For Microsoft Defender Zero-Day

Researcher Chaotic Eclipse released ShieldCrash, a PoC showing Microsoft Defender's CVE-2026-69414 patch is incomplete, enabling arbitrary file reads as SYSTEM.

Security researcher Chaotic Eclipse published ShieldCrash, a proof-of-concept exploit for the Microsoft Malware Protection Engine privilege escalation vulnerability CVE-2026-69414 (ShieldBreak). The PoC performs arbitrary file reads with SYSTEM privileges on all supported Windows versions, including systems running the September 2026 security updates and Malware Protection Engine version 1.1.26080.3. The researcher claims Microsoft's patch fixed several exploit paths but missed a specific condition that still enables the attack. His recent releases also include zero-day PoCs targeting Nvidia, Kaspersky, Avast, and CrowdStrike Falcon.

Security Affairsupdated · 5d agofirst · 6d agoExploit / PoC 8 sourcesCVE-2026-69414

New Microsoft Defender 'ShieldCrash' zero-day grants SYSTEM access

Researcher Nightmare Eclipse released 'ShieldCrash', a zero-day exploit for Microsoft Defender that grants attackers SYSTEM-level access.

An anonymous researcher known as Nightmare Eclipse published a zero-day exploit for Microsoft Defender, dubbed 'ShieldCrash', that yields SYSTEM-level access. The release came immediately after Microsoft rolled out its September 2026 Patch Tuesday security updates. No CVE identifier has been assigned publicly and no in-the-wild exploitation has been reported yet. Microsoft Defender ships by default on Windows, so potential exposure is broad until Microsoft patches the flaw.

BleepingComputer · 6d agoExploit / PoC

Researcher Drops New Microsoft Defender PoC Showing ShieldBreak Patch Can Be Bypassed

Researcher Chaotic Eclipse released a PoC showing CVE-2026-69414's patch is bypassable, allowing arbitrary file reads as SYSTEM on current Windows.

The researcher known as Chaotic Eclipse published a proof-of-concept for a zero-day in Microsoft Defender, dubbed ShieldCrash, assessed as a patch bypass for ShieldBreak (CVE-2026-69414, CVSS 7.8). The PoC demonstrates an arbitrary file read as SYSTEM with the latest Windows installed, and all supported desktop versions are said to be impacted. Microsoft patched the original issue in Microsoft Malware Protection Engine 1.1.26080.3, which updates automatically. The same researcher recently released PoCs for flaws in CrowdStrike Falcon Sensor, Kaspersky, Avast Antivirus and NVIDIA.

The Hacker Newsupdated · 5d agofirst · 6d agoExploit / PoC 8 sourcesCVE-2026-694141

Four REVSTEALER-Linked Modules Disable Windows Update and Defender to Run a Crypto Miner

Elastic documents four persistent REVSTEALER-linked tools (ProManager, WinUpdate, SoftManager, LockAppHost); LockAppHost disables Windows Update and Defender to run a crypto miner.

Elastic Security Labs identified four previously unreported executables tied to REVSTEALER, a commercial Windows infostealer sold since at least February 2026: ProManager, WinUpdate, SoftManager, and LockAppHost. LockAppHost abuses CMSTP for elevation, adds Microsoft Defender exclusions, disables five Windows Update services and 13 scheduled tasks, then hides a miner in legitimate Windows processes; other modules steal wallets, clipboard-swap crypto addresses, and turn victims into reverse proxies. The components share REVSTEALER tradecraft including packer, runtime function resolution, and Polygon smart-contract backup configuration (EtherHiding). Elastic's detection rule matched about 4,700 VirusTotal samples over the past year; distribution uses hijacked YouTube channels promoting game cheats and a fake 'Claude Opus 5 Free Desktop' app.

The Hacker News · 9d agoMalware in the wild

Rogue ScreenConnect Installations Across Unrelated Hosts Suggest Worm-Like Activity

Huntress observed rogue ScreenConnect deployments with worm-like VBScript propagation across unrelated organizations, prompting a ConnectWise advisory on file transfer behavior.

Huntress identified multiple incidents in late August 2026 where social engineering led to rogue ScreenConnect remote access clients deployed on victim machines, which then spawned wscript.exe to run four VBScript payloads (1.vbs through 4.vbs) for profiling, telemetry collection, and persistence via a WindowsServiceHost Run key. Modified ScreenConnect clients propagated the VBScript chain to connected endpoints, creating worm-like spread. ConnectWise published an advisory on September 3, 2026, confirming an issue affecting file transfer behavior in both cloud and on-premises ScreenConnect deployments, with a CVE and fix expected within the week; partners were advised to review and disable TransferFiles permissions in the interim.

Huntress · 12d agoExploit / PoC in the wild

Researcher Releases FalconFlank PoC Showing Privilege Escalation in CrowdStrike Falcon

Researcher Chaotic Eclipse released FalconFlank, a zero-day privilege escalation PoC abusing CrowdStrike Falcon's Office macro remediation; CrowdStrike is investigating and issued a tech alert.

Researcher Chaotic Eclipse published FalconFlank, a proof-of-concept zero-day local privilege escalation in CrowdStrike Falcon Sensor that abuses the Microsoft Office malicious macros remediation feature, tested on fully updated Windows 11 25H2 and Windows Server 2025. CrowdStrike said it is investigating, advised disabling the Microsoft Office File Suspicious Macro Removal policy, and pointed customers to a FalconFlank tech alert, noting cloud anti-malware protection remains active. The article also covers related PoCs from the same researcher: HardBreacher against Kaspersky (fixed via update), ShieldBreak (CVE-2026-69414) against Microsoft Defender, an unpatched patch bypass of CVE-2026-50656, GreenSection against NVIDIA, and PrettyPrague against Avast, which Gen Digital patched in versions 26.7.11086 and 26.8.11125.

Fake Software Installers Disable Windows Update and Weaken Microsoft Defender

Fake software-download sites distribute installers that disable Windows Update and weaken Defender, attributed to China-linked cluster Silver Fox.

Microsoft says an active campaign uses counterfeit vendor websites on .com.cn and .hl.cn infrastructure with Chinese-language lures to deliver server-side generated installers that establish scheduled-task persistence, add Defender exclusions, delete shadow copies, and stop services including wuauserv, UsoSvc, uhssvc and WaaSMedicSvc. Victims span healthcare, manufacturing, gaming, technology, logistics, government and education, primarily China-based operations of multinationals and Chinese-speaking users. Microsoft assesses with moderate confidence the activity matches the Silver Fox (Yinhu) cluster, historically tied to Gh0st RAT and ValleyRAT, with C2 over non-standard ports like 5090 and 7088-7090 via domains iualef[.]net and oijfwe[.]net. Kaspersky separately detailed a QN Wallpaper DLL-sideloading chain delivering ValleyRAT.

The Hacker News · 13d agoMalware in the wild

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 · 15d agoMalware in the wild

Aurora Ransomware Operators Use Cursor AI in Attacks Against 10 Targets

Aurora ransomware operators used Cursor AI running Claude Sonnet to plan and execute intrusions against dozens of organizations in nine countries.

CloudSEK and Gambit Security analyzed exposed infrastructure tied to the Russian-speaking Aurora (Aur0ra) group, revealing months of activity against more than 20 organizations across nine countries between April and July 2026, with 33 victims listed by Ransomware.Live. The operator used the Cursor agentic coding assistant to plan attacks in Russian, including an AD CS exploitation plan, and Gambit observed Cursor Agent (running Anthropic's Claude Sonnet) performing hands-on exploitation tasks such as Nmap scanning, NetExec enumeration, NTLM relay, and certificate attacks against 10 targets. Attacks begin with email bombing plus IT help desk vishing via Xray-core, followed by SMB/LDAP/WinRM/RDP lateral movement, log clearing, Defender disabling, and exfiltration; the Windows and Linux/ESXi encryptors are built from a single Zig codebase, with shadow copy deletion and VM-killing before encryption.

The Hacker News · 15d agoRansomware in the wild1

Weedhack Malware Spreads via Fake Minecraft Clients and SEO Poisoning

McAfee Labs reports Weedhack malware spread via spoofed Minecraft client websites using SEO poisoning, with over 6,300 blocked access attempts.

McAfee Labs found multiple lookalike websites impersonating legitimate Minecraft clients (Glazed, Radium, Meteor, Nova, Xenon) still distributing Weedhack, a multi-stage malware whose JAR payloads collect system information, add Microsoft Defender exclusions, and steal sensitive data. Distribution relies on SEO poisoning to outrank official sources, plus Discord, MediaFire, GitHub, and Minecraft hosting sites; nearly half of malicious URLs were Discord links. One fake site was built with the AI website builder Lovable, and McAfee blocked more than 6,300 access attempts to malicious sites.

The Hacker News · 22d agoMalware in the wild

Microsoft Defender's Own Driver Can Be Weaponized to Delete Security Software at Boot

Check Point revealed BTR Reforged, a technique weaponizing Microsoft Defender's built-in BTR.sys driver to delete security software at boot without exploiting any vulnerability.

Check Point Research disclosed BTR Reforged, a technique that abuses BTR.sys, a legitimately signed Windows Defender boot-time remediation driver, to perform arbitrary kernel-level file and registry operations on Windows 7 through Windows 11 25H2 without exploiting a software flaw. The BTR_CLI proof-of-concept tool, presented at Black Hat USA 2026 and DEF CON 34, installs the driver via direct registry writes and executes deletions during the boot-time 'golden window' before Defender's user-mode services start, demonstrated by deleting the full Defender stack on a patched Windows 11 machine. Exploitation requires SeLoadDriverPrivilege; Microsoft confirmed it does not meet criteria for immediate servicing and no patch is planned. No evidence of real-world abuse was found, and related indicators of compromise via Sysmon events were published.

The Hacker News · 25d agoToolsCVE-2021-240921

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 · 25d agoThreat actor1

BTR Reforged: Weaponizing Defender’s Remediation Driver as a Kernel Operation Primitive

Check Point shows attackers can abuse Microsoft Defender's signed remediation driver for arbitrary Ring 0 file and registry operations without exploiting any vulnerability.

Check Point Research presents BTR Reforged, a technique that repurposes Microsoft Defender's trusted remediation driver into an attacker-controlled kernel operation primitive. The signed driver can be instructed to execute arbitrary file and registry operations from Ring 0 without exploits, vulnerabilities, or memory corruption. The work demonstrates how trusted security components can be turned into attacker primitives, which is relevant for defenders assessing driver abuse risks.

Check Point Research · 26d agoResearch

ShieldBreak Zero-Day PoC Claims Microsoft Defender Patch Bypass With SYSTEM Access

Researcher Chaotic Eclipse released ShieldBreak PoC, a claimed patch bypass for Microsoft Defender flaw CVE-2026-50656, now tracked as CVE-2026-69414.

Researcher Chaotic Eclipse released a PoC for ShieldBreak, a claimed full patch bypass of Microsoft Defender flaw CVE-2026-50656 (RoguePlanet), which can yield SYSTEM privileges. Independent researchers Kevin Beaumont and Will Dormann validated the exploit on Windows 11 25H2 and Windows Server 2025, noting it requires Defender to be enabled. Microsoft assigned CVE-2026-69414 (CVSS 7.8) with an 'Exploitation More Likely' assessment and is investigating, but has not yet released a patch. The article also notes CISA's KEV addition of the actively exploited Windows AFD.sys flaw CVE-2026-68820.

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 · 29d agoThreat 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

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

Akira Hits Safe Mode: Ransomware Rebooting Around EDR

Huntress documents an Akira ransomware affiliate rebooting endpoints into Windows Safe Mode to evade EDR and Defender, though Safe Mode broke the ransomware.

Huntress observed an Akira ransomware affiliate rebooting victim machines into Windows Safe Mode to disable EDR and Microsoft Defender before deploying ransomware. In an ironic twist, Safe Mode also prevented the ransomware from executing properly. The post walks through the full attack chain and the defensive lessons.

Huntress · Aug 12, 2026Ransomware in the wild

ShieldBreak: New Windows Zero-Day Bypasses Microsoft’s RoguePlanet Patch

Researcher Chaotic Eclipse published a PoC bypassing Microsoft's CVE-2026-50656 Defender patch, enabling SYSTEM-level code execution on fully patched Windows systems.

Security researcher Chaotic Eclipse released a proof-of-concept for ShieldBreak, a Microsoft Defender zero-day that fully bypasses the patch for CVE-2026-50656 (RoguePlanet), a race condition in the Malware Protection Engine (mpengine.dll) allowing SYSTEM-level code execution. The PoC was tested on Windows 11 25H2 and Windows Server 2025 with a 100% success rate, and Windows 10 is also vulnerable though not supported by the PoC; the flaw may also leak 8 bytes of memory. Microsoft's MSRC had criticized the researcher's repeated uncoordinated disclosures, including YellowKey (BitLocker bypass), GreenPlasma, and LegacyHive (User Profile Service LPE).

Security Affairs · Aug 12, 2026Exploit / PoCCVE-2026-50656

Microsoft patches 400+ vulnerabilities, one zero-day under attack (CVE-2026-68820)

Microsoft's August 2026 Patch Tuesday fixes 400+ vulnerabilities, including an actively exploited Windows zero-day (CVE-2026-68820) used by North Korean attackers.

Microsoft's August 2026 Patch Tuesday fixes over 400 vulnerabilities, including CVE-2026-68820, a use-after-free in the Windows Ancillary Function Driver exploited in the wild by North Korean actors deploying a kernel-mode rootkit in Operation Dream Job. Critical unauthenticated remote code execution flaws in Microsoft QUIC (CVE-2026-62815) and Windows DNS (CVE-2026-62878) were also patched, alongside a SharePoint RCE chain combining CVE-2026-63520 with CVE-2026-55040. Researcher Nightmare-Eclipse released ShieldBreak, a PoC bypassing the July RoguePlanet Microsoft Defender patch (CVE-2026-50656), confirmed working by Will Dormann on Windows 11.

Help Net Security · Aug 12, 2026Exploit / PoC in the wildCVE-2026-68820CVE-2026-62832CVE-2026-72971+6 CVEs

Related CVEs

  • Local Elevation of Privilege in Microsoft Defender Malware Protection Engine
    CVE-2026-69414, publicly dubbed 'ShieldBreak', is a high-severity (CVSS 3.1: 7.8) elevation-of-privilege flaw in the Microsoft Malware Protection Engine (MMPE) that powers Microsoft Defender, rooted in improper access control and improper privilege management (CWE-284/CWE-269). It is triggered locally: an attacker who already holds low privileges on the machine needs no user interaction (AV:L/AC:L/PR:L/UI:N) to trip the engine's flawed access checks, and successful exploitation yields high impact to confidentiality, integrity, and availability. News coverage reports public PoCs released under the 'ShieldBreak'/'ShieldCrash' names demonstrating SYSTEM-level access on Defender-protected Windows systems, including claims that the shipped patch can be bypassed and arbitrary files read as SYSTEM. Because MMPE ships as the scan engine inside Microsoft Defender, effectively every Defender-protected Windows 10/11 endpoint and server is potentially affected, though the source data specifies no affected engine version ranges. There is no confirmed in-the-wild exploitation (EPSS 0.6%, absent from CISA KEV), but given the public PoC claims, defenders should assume working exploit code exists.
    · Microsoft Malware Protection Engine (used in Microsoft Defender)mass
  • Microsoft is aware of an elevation of privilege in the Microsoft Malware Protection Engine in Microsoft Defender publicly referred to as "RoguePlanet ".
    Microsoft is aware of an elevation of privilege in the Microsoft Malware Protection Engine in Microsoft Defender publicly referred to as "RoguePlanet ".
    · microsoft malware protection engine PoC
  • Authentication Bypass in Microsoft SharePoint Server
    Microsoft SharePoint Server is affected by a weak authentication vulnerability (CWE-1390) that allows an unauthorized attacker to bypass a security feature over a network. Per the CVSS vector, exploitation requires no privileges and no user interaction with low attack complexity, so any unauthenticated attacker with network access to a vulnerable server can trigger it remotely. Impact to confidentiality and integrity is rated high (CVSS 9.1, critical), meaning the bypass effectively grants the attacker access that authentication should have prevented, with no direct availability impact. All organizations running on-premises Microsoft SharePoint Server are potentially affected; the source data does not specify affected version ranges or fixed builds, so defenders should consult Microsoft's advisory for those details. The flaw is under active exploitation: a public proof-of-concept is available on GitHub, attackers began exploiting it after the PoC went public, and CISA added it to the Known Exploited Vulnerabilities catalog on 2026-08-18 (EPSS ~40%, 99th percentile; ransomware association unknown).
    · Microsoft SharePoint Server KEV PoC ×2mass
  • Use-After-Free Local Privilege Escalation in Microsoft Windows WinSock AFD Driver
    CVE-2026-68820 is a use-after-free (CWE-416) in the Windows Ancillary Function Driver for WinSock (afd.sys), the kernel component that handles Winsock socket operations. A local, authenticated attacker can trigger the memory corruption through crafted socket activity, and the high attack-complexity score (AV:L/AC:H/PR:L) indicates exploitation requires a specific, likely race-sensitive sequence of operations. Successful exploitation elevates privileges to SYSTEM, giving the attacker full control of the host, and public reporting describes deployment of a backdoor after privilege escalation. Virtually every Windows 10, Windows 11, and Windows Server (2012-2022) installation ships this driver, so the affected population is essentially the entire supported Windows installed base. The flaw is being exploited in the wild: CISA added it to the KEV on 2026-08-11, Microsoft fixed it in the August 2026 Patch Tuesday release, and reporting ties active exploitation to North Korea's Lazarus group, who paired the zero-day with fake job-offer lures.
    · Microsoft Windows Ancillary Function Driver for WinSock (afd.sys) as shipped with the Windows versions listed below · Microsoft Windows 10 1607, 1809, 21H2, 22H2 KEVmass
  • Unauthenticated RCE in Microsoft SharePoint Server
    CVE-2026-63520 is an improper input validation flaw (CWE-20) in Microsoft Office SharePoint, affecting on-premises SharePoint Server deployments. A remote, unauthenticated attacker can trigger the flaw by sending improperly validated input to the SharePoint service over the network; the high attack complexity (AC:H) indicates exploitation depends on specific conditions, but no privileges or user interaction are required. Successful exploitation results in arbitrary code execution on the server, with high impact to confidentiality, integrity, and availability — effectively full compromise of the SharePoint host. Organizations running self-hosted SharePoint Server are in scope; SharePoint Online/Microsoft 365 is not listed in the affected products. The issue is patched as of Microsoft's Patch Tuesday (headlines mark it FIXED), with Rapid7 analysis and a researcher-disclosed exploit chain available, but there is no public PoC, no CISA KEV listing, and no confirmed in-the-wild exploitation; EPSS puts exploitation probability at 2.9% (86th percentile).
    · Microsoft SharePoint Server (Office SharePoint, on-premises)mass
  • Local Privilege Escalation via Link Following in Windows User Profile Service
    CVE-2026-62832 is a local privilege escalation flaw (CWE-59, improper link resolution, or 'link following') in the Windows User Profile Service. An attacker who already holds a limited local account on an affected machine can cause the service to follow a symbolic link or junction before it validates file access, so the service performs file operations with elevated rights. Successful exploitation grants elevated privileges on the local system — typically up to administrator/SYSTEM level — with no user interaction required. Affected platforms include Windows 10 21H2 and 22H2, Windows 11 23H2 through 26H1, and Windows Server 2022 and 2025, which together span essentially the entire supported Windows estate. As of this analysis there is no public proof-of-concept, no CISA KEV listing, and no confirmed in-the-wild exploitation of this specific flaw; EPSS estimates a 3.3% (88th percentile) chance of exploitation within 30 days, although Microsoft's August 2026 Patch Tuesday fixed 400+ vulnerabilities and a separate zero-day (CVE-2026-68820) is under active attack.
    · microsoft Windows 10 21H2 · microsoft Windows 10 22H2mass
  • Local Tampering via Link-Following Flaw in Windows 11 26H1 Container Isolation Driver
    CVE-2026-72971 is a link-following flaw (CWE-59) in the Windows Container Isolation FS Filter Driver (unionfs.sys) on Windows 11 26H1: the driver performs file access without fully verifying that the path is not redirected through a symbolic link or junction. A local attacker who already holds low-privilege access (CVSS AV:L/PR:L, no user interaction required) can plant a malicious link at a location the driver processes, causing it to follow the link and act on an attacker-chosen target. The attacker gains tampering capability, which the CVSS scores as High integrity impact with no confidentiality or availability impact, meaning they can modify or overwrite files their account could not normally change. Any Windows 11 26H1 system is in scope per the CVE data, with the highest practical risk on shared or multi-user hosts and machines using container isolation features where unionfs.sys is active. No active exploitation is known: the CVE is not in CISA KEV, no public proof-of-concept exists, and EPSS puts 30-day exploitation probability at about 0.5%; the related news shows Microsoft's August 2026 Patch Tuesday shipped 400+ fixes, and defenders should confirm their devices received the unionfs.sys patch.
    · microsoft Windows 11 26H1 (Container Isolation FS Filter Driver, unionfs.sys)mass
  • SSRF Privilege Elevation in Microsoft Exchange Online
    CVE-2026-65801 is a server-side request forgery (CWE-918) in Microsoft's cloud-hosted Exchange Online service that an unauthorized attacker can reach over the network without credentials or user interaction. A crafted request causes Exchange Online server components to issue requests toward internal service endpoints, and the scope-changed CVSS 3.1 vector (S:C with high confidentiality, integrity, and availability impact) indicates the resulting privilege elevation extends beyond the initially targeted component. A successful attacker gains elevated privileges within the Exchange Online service, potentially enabling broader access to mailbox data and service functionality. All organizations with mailboxes hosted in Exchange Online are in scope; because this is a flaw in Microsoft's managed service, customers cannot patch it themselves and depend on Microsoft's service-side remediation. Exploitation has not been publicly confirmed: the flaw is not in CISA KEV, no public proof-of-concept is known, and EPSS estimates only about a 0.5% probability of exploitation within 30 days.
    · Microsoft Exchange Online (hosted cloud service) Microsoft-managed cloud service; no customer-deployed version numbers apply (none provided in the data)mass
  • Use-After-Free RCE in Windows DNS Server
    CVE-2026-69730 is a use-after-free memory corruption flaw (CWE-416) in the Windows DNS service that allows an unauthenticated, remote attacker to execute arbitrary code by sending crafted network traffic to the affected system. Because the flaw is network-exploitable with no privileges or user interaction required (CVSS 3.1 9.8), any system running the vulnerable DNS service is a direct target. Successful exploitation would give the attacker code execution in the context of the DNS service, which on Windows Server typically runs with high privileges such as SYSTEM, and could enable wormable spread between vulnerable hosts. Affected organizations are those running the Windows DNS Server role — a component deployed on virtually all Windows Server domain controllers and on dedicated Windows DNS servers, especially those exposed to untrusted networks. As of the September 2026 Patch Tuesday release, there is no known public proof-of-concept, the flaw is not listed in CISA's KEV, and it has not been confirmed exploited in the wild, though it was flagged among roughly 20 'wormable' bugs and described in press coverage as a successor to the 2020 SigRed Windows DNS RCE.
    · Microsoft Windows DNS Server role (Windows Server)mass
  • Kerberos Capture-Replay Authentication Bypass in Microsoft Windows (RCE)
    CVE-2026-69676 is a capture-replay authentication bypass (CWE-294) in the Windows Kerberos implementation, disclosed by Microsoft as part of the September 2026 Patch Tuesday. An attacker who is already authorized (low-privilege credentials) can replay captured authentication material over the network to bypass authentication checks. Successful exploitation results in remote code execution, with high impact on confidentiality, integrity, and availability (CVSS 3.1 score of 8.8). Any organization running Windows in an Active Directory environment is potentially affected, since Kerberos is the default authentication protocol for Windows domains. As of this analysis there is no known public proof-of-concept, the flaw is not in CISA's KEV catalog, and EPSS estimates only a ~1.2% chance of exploitation within 30 days, though it shipped in a record-sized Patch Tuesday release alongside two actively exploited zero-days.
    · Microsoft Windows (Kerberos authentication implementation)mass

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