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.
One Click on a Malicious Link Lets Hackers Backdoor Sogou Input Method Users
Actively exploited one-click flaw in Sogou Input Method (CVE-2026-51990) let UNC3569 deploy the GRAYRABBIT espionage backdoor on Windows.
Gen Digital researchers found three weaknesses in Sogou Input Method's sgbiz protocol handler that chain into a one-click RCE running with the signed-in user's permissions. UNC3569 used the chain in an active intrusion, leveraging an unsandboxed Chromium 80 embedded browser, the known V8 flaw CVE-2021-38003, and DLL sideloading via 7-Zip to deploy the GRAYRABBIT backdoor. Tencent fixed the issue in version 16.3.0.3498 within 12 days of disclosure; Sogou is used by hundreds of millions of people, mainly in China.
Google Chrome 153 Released With 230 Security Fixes and Zero-Day Exploited in the Wild
Google released Chrome 153 with 230 security fixes, patching CVE-2026-87491, a V8 out-of-bounds write zero-day actively exploited in the wild.
Google shipped Chrome 153 (153.0.8010.36/.37) for Windows, macOS, and Linux with 230 security fixes, including CVE-2026-87491, a medium-severity V8 out-of-bounds write being exploited in the wild. The release also fixes five critical vulnerabilities: four in WebGL (two use-after-frees, an out-of-bounds write, a buffer overflow) and one use-after-free in Cast. High-severity V8 use-after-free and type-confusion defects are among the fixes, and Google has restricted technical details until most users are patched. Administrators should verify deployed versions on managed endpoints, as Chrome-derived browsers may follow different patch schedules.
PaperCut Flaws Exploited in Attacks on U.S. and European Schools
Attackers are chaining recently disclosed PaperCut flaws CVE-2026-81578 and CVE-2026-82078 to steal credentials and create privileged accounts at US and European schools.
Arctic Wolf researchers observed threat actors exploiting PaperCut servers via CVE-2026-81578 and CVE-2026-82078, chaining an authentication bypass with remote code execution. Post-exploitation included creating a privileged account named Administrator17, downloading credential-harvesting tools with certutil, Meterpreter Java payloads, and registry hive collection to recover the Windows BootKey and reach the SAM database. PaperCut disclosed active exploitation on August 27, 2026, and CISA added both flaws to its Known Exploited Vulnerabilities catalog on August 31. PaperCut has a history of exploitation, including attacks that delivered LockBit ransomware.
NSA, CISA, FBI, DOE, and EPA Warn of Active AI
Five US agencies warn of active AI-assisted attacks on internet-exposed Siemens S7 PLCs across critical infrastructure, using disguised snap7 scripts for pre-positioning reconnaissance.
NSA, CISA, FBI, DOE, and EPA issued joint advisory CISA AA26-231A warning of an active hacking campaign against Siemens S7-series PLCs, from S7-200 through S7-1500 F-series, across US critical infrastructure. Threat actors use internet scanning services such as Censys and ZoomEye to locate exposed controllers, then perform read operations over S7comm on TCP port 102 using the legitimate snap7.dll and python-snap7 libraries, disguising AI-generated exploitation scripts as monitoring tools. The agencies assess the activity as pre-positioning ahead of possible process disruption, equipment damage, or safety incidents in Energy, Water, Critical Manufacturing, Chemical, Food and Agriculture, and Commercial Facilities sectors.