StyleSmuggler: The Magento Zero-Day Behind New Store Attacks
Sansec reports actively exploited Magento/Adobe Commerce zero-day StyleSmuggler enabling unauthenticated RCE and Rust backdoor installation on fully patched stores since September 4.
Sansec discovered StyleSmuggler, an unpatched zero-day in Magento Open Source and Adobe Commerce, affecting all current versions including 2.4.7, 2.4.8 and 2.4.9, with attacks observed since September 4. The two-stage attack poisons Magento's template system via the styles property and executes the injected PHP during 'Payment Transaction Failed Reminder' email rendering, working even when email delivery fails and when sessions are moved to Redis. Successful compromise installs a lightweight Rust backdoor disguised as fc-cache or chronyd that beacons every 60 seconds with 48-byte UDP packets to NTP port 123 at ntp.timesync.to. A second attacker deployed a PHP web shell in product-image cache directories, hidden behind 404 responses unless a correct X-Cache-Token header is present.
Attackers Chain Two PaperCut Flaws to Execute Code Without Authentication
Attackers chain PaperCut NG/MF flaws CVE-2026-81578 and CVE-2026-82078 for unauthenticated RCE; exploitation observed and a second emergency patch issued.
Two flaws in PaperCut NG and MF — CVE-2026-81578 (CVSS 8.8, improper access control enabling auth bypass) and CVE-2026-82078 (CVSS 9.4, unsafe dynamic class loading) — are being chained for unauthenticated remote code execution. Huntress observed limited exploitation on two customer environments, including Base64-encoded commands, 'whoami & ver' fingerprinting, SimpleHelp execution, and AnyDesk installation for persistence. PaperCut released a second emergency patch for v24, v25, and v26, but watchTowr reports additional patch bypasses may still affect the latest version. Shared IoCs include crafted jdbc strings in server.log and attacker-written .class/.cmd files.
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.