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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

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

Microsoft Links 30+ Rotating Domains to MacSync Stealer Infrastructure

Microsoft links 30+ rotating domains to the MacSync macOS infostealer, confirming active credential and file exfiltration through chunked HTTP PUT uploads.

Microsoft Defender Experts correlated 30+ domains with MacSync Stealer, requiring aligned endpoint and network behaviors (process ancestry, command-line patterns, /curl/, /dynamic?txd=, and /gate?buildtxd= paths, API-key headers, chunked HTTP PUT parameters) to link infrastructure. Execution begins from an interactive zsh session consistent with ClickFix social engineering, with curl retrieving and Base64/gunzip decoding the payload, followed by collection of Keychain data, browser credentials, SSH keys, AWS credentials, Kubernetes configs, and Apple Notes. Data is zipped to /tmp/osalogging.zip, chunked, uploaded via HTTP PUT, and artifacts are deleted afterward; the analysis builds on RST Cloud's May 8 findings and overlaps with Microsoft's earlier 250+ domain ClickFix campaign distributing MacSync and Atomic Stealer (AMOS).

The Hacker News · 28d agoMalware in the wild

September 2026 Patch Tuesday roundup: Plugs for two zero day holes among almost 1,000 fixes in Windows

Microsoft's September 2026 Patch Tuesday ships 964 fixes including two exploited Windows zero-days (CVE-2026-85880, CVE-2026-81963) and a wormable DNS RCE.

Microsoft's September 2026 Patch Tuesday includes 964 Microsoft vulnerabilities requiring customer action, a record attributed to AI-assisted bug discovery, plus 174 third-party/open-source and 23 Chromium/Edge CVEs. Two zero-days are exploited in the wild: CVE-2026-85880, a Windows ALPC heap overflow enabling AppContainer sandbox escape and privilege escalation, and CVE-2026-81963, a Windows Update Stack escalation to SYSTEM. CVE-2026-69730, an unauthenticated Windows DNS RCE, is not yet exploited but Microsoft expects exploitation, and roughly 20 bugs could be wormable. Separately, SAP issued a critical CVSS 10.0 fix for the EPP component used in S/4HANA and NetWeaver.

CSO Online · 7d agoVulnerability in the wildCVE-2026-85880CVE-2026-81963CVE-2026-69730+2 CVEs1

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

Microsoft posts nearly 1,000 bugs for Patch Tuesday as CISA warns two being exploited

CISA confirms exploitation of two Windows zero-days among 973 Microsoft patches; 22,000 Exchange servers remain unpatched.

Microsoft's September Patch Tuesday sets a record with 973 vulnerabilities, and CISA confirms CVE-2026-81963 and CVE-2026-85880 are being exploited, giving federal agencies until September 22 to patch. Nightwing estimates over 22,000 corporate Exchange servers are unpatched against weaponized exploit code. Analysts describe CVE-2026-81963 as an early link in ransomware chains where phishing leads to privilege escalation, and note year-to-date Microsoft disclosures exceed 2,600 bugs.

The Record · 7d agoExploit / PoC in the wildCVE-2026-81963CVE-2026-85880