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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

CVE-2026-50522: Microsoft SharePoint Server RCE Vulnerability

CVE-2026-50522 is an unauthenticated .NET deserialization RCE in SharePoint Server Subscription, 2019, and 2016; Microsoft patched it July 14, 2026.

CVE-2026-50522 (CWE-502) lets unauthenticated attackers send crafted serialized .NET payloads to network-accessible SharePoint endpoints, triggering gadget-chain deserialization and remote code execution under the privileged SharePoint service account. It affects SharePoint Server Subscription Edition, SharePoint Server 2019, and SharePoint Server 2016 Enterprise; Microsoft published the advisory on July 14, 2026. The EPSS score is 20.346%, but no public PoC exists and the flaw is not in CISA's KEV catalog at publication. Mitigations include applying Microsoft updates, rotating SharePoint machine keys, enabling AMSI, and restricting internet exposure.

Microsoft discloses two actively exploited zero-days among 974 vulnerabilities

Microsoft patches 974 flaws in record Patch Tuesday, including two actively exploited Windows zero-days enabling privilege escalation.

Microsoft's largest-ever Patch Tuesday addresses 974 vulnerabilities, with CVE-2026-81963 (Windows Update Stack) and CVE-2026-85880 (Windows Advanced Local Procedure Call) exploited before disclosure. Both zero-days carry CVSS 7.8 ratings and allow privilege escalation. More than 10% of the defects are rated critical, and researchers attribute the record volume to AI-assisted vulnerability discovery without a matching rise in active exploitation.

CyberScoop · 8d agoExploit / PoC in the wildCVE-2026-81963CVE-2026-85880

Microsoft Shatters Patch Tuesday Record With 974 CVE Fixes in September 2026

Microsoft's September 2026 Patch Tuesday fixes a record 974 CVEs, including two actively exploited Windows zero-days, CVE-2026-85880 and CVE-2026-81963.

Microsoft fixed a record 974 CVEs in its September 2026 Patch Tuesday, surpassing the previous record of 570 in July 2026, with Windows affected by 723 flaws and Office by 111, including 119 critical vulnerabilities. Two zero-days are actively exploited: CVE-2026-85880, a 7.8 heap-based buffer overflow in Windows ALPC allowing AppContainer privilege escalation, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack enabling local privilege escalation. Microsoft attributed the update surge partly to agentic AI tools used to discover zero-day vulnerabilities, and researchers highlighted critical RCE flaws in Windows DNS, DHCP and Deployment Services as priorities.

The September 2026 Security Update Review

ZDI's September 2026 Microsoft update review lists two already-exploited Windows EoP zero-days and dozens of critical RCEs across Office, SQL Server, and Windows services.

The review catalogs Microsoft's September 2026 fixes, marking CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack) as already exploited elevation-of-privilege issues. It also lists critical RCE flaws in Office, Word, Excel, PowerPoint, Outlook, SQL Server, Windows DNS, DHCP and Failover Cluster, plus graphics component RCEs. Azure-side fixes include Entra ID, Copilot Studio, Azure AI Language and Azure AD B2C elevation-of-privilege flaws.

Windows Remote Desktop Client Vulnerability Allows Attackers to Execute Remote Code

Microsoft patched CVE-2026-69485, an 8.8 CVSS RCE flaw in the Windows Remote Desktop Client affecting Windows 10/11 and Server 2016-2025.

Microsoft's September 2026 updates fix CVE-2026-69485, an Important-rated remote code execution vulnerability (CVSS 3.1: 8.8, temporal 7.7) in the Windows Remote Desktop Client caused by use of an uninitialized resource. An authenticated attacker with low privileges could send a specially crafted network request to execute code on an affected server, with no user interaction required. Microsoft says the flaw was not publicly disclosed before patching and rates exploitation as 'Less Likely' with no evidence of active exploitation. Affected products span Windows Server 2016, 2019, 2022 and 2025 and Windows 10 (1607-22H2) and Windows 11 (23H2-26H1), with fixes delivered via KBs including KB5123099, KB5122876 and KB5122882.

Four groups caught using the same Chrome and Windows exploit kit

Proofpoint reports at least four hacking groups, some China-linked, share the BlueMoon exploit kit chaining Chromium and Windows kernel vulnerabilities to install malware.

Proofpoint named the nearly identical kit BlueMoon; it chains two Chromium vulnerabilities with one Windows kernel privilege-escalation flaw affecting Windows 10 (October 2018 Update and 2004), Windows Server 2019 and 2022, and the initial Windows 11 release. All three vulnerabilities received patches within 24 hours of the activity. The kit is being actively used by at least four hacking groups, some with Chinese government ties. Proofpoint links the rapid, visible sharing of a historically rare full browser exploit chain to the Chromium supply-chain patch gap and AI-assisted exploit development.

Proofpoint Threat Insight · 7d agoExploit / PoC in the wild 3 sources1

Microsoft patches a record 972 vulnerabilities, 112 of them critical

Microsoft's September Patch Tuesday fixes a record 972 vulnerabilities, 112 rated critical, including two zero-days in Windows components.

Microsoft's September 2026 release patched roughly 972 vulnerabilities (997 including ported Chromium fixes for Edge), a record, with 112 rated critical. Notable flaws include two zero-days: CVE-2026-81963 in the Windows update service and CVE-2026-85880 in the Windows Advanced Local Procedure, with no public information on exploitation breadth. Microsoft has fixed 2,760 vulnerabilities in 2026, more than double last year's total, which ZDI's Dustin Childs attributes to AI-assisted discovery becoming the 'new normal'.