Microsoft Patch Tuesday, September 2026 Security Update Review
Microsoft's September 2026 Patch Tuesday fixes 974 vulnerabilities, including 113 critical and two actively exploited Windows privilege escalation flaws.
Microsoft's September 2026 Patch Tuesday fixes 974 vulnerabilities, its largest release ever, including 113 critical and 860 important, covering Windows HTTP.sys, Hyper-V, Entra ID, Exchange Server, Office, DNS, and more. Two zero-days are confirmed exploited in the wild: CVE-2026-81963 (Windows Update Stack EoP) and CVE-2026-85880 (ALPC heap overflow), both letting authenticated attackers gain SYSTEM privileges. Notable criticals include an Entra ID authentication bypass (CVE-2026-62916) and multiple Windows DNS Server and Office remote code execution flaws.
Microsoft Teams for Android Vulnerability Exposes Sensitive Information
Microsoft patched CVE-2026-65812 in Teams for Android, an information-disclosure flaw that can leak credentials under specific conditions.
Microsoft fixed CVE-2026-65812, rated Important, which can insert sensitive information such as credentials into data sent by Microsoft Teams for Android (build 1416/1.0.0.2026133602). Exploitation is remote and low-complexity, requires low privileges plus user interaction, and impact is limited to high confidentiality impact. Microsoft says exploitation is less likely, with no public PoC, disclosure, or in-the-wild exploitation; the fix ships via the Teams app update on Google Play. Ofek Levin of Enclave reported the flaw through coordinated vulnerability disclosure.
Microsoft Patch Tuesday Update September 2026 – 974 Vulnerabilities Fixed, Including 2 Zero-Days
Microsoft's September 2026 Patch Tuesday fixes 974 vulnerabilities across Windows and Office, including two actively exploited Windows privilege-escalation zero-days.
Microsoft's September 2026 Patch Tuesday addresses 974 vulnerabilities spanning Windows, Office, SQL Server, SharePoint, Exchange, Azure, and developer tools. Two Windows zero-days are confirmed exploited in attacks: CVE-2026-85880, a Windows ALPC elevation-of-privilege flaw, and CVE-2026-81963, a Windows Update Stack privilege-escalation flaw involving link following. The release also includes Critical fixes for Windows Secure Kernel Mode, VBS Enclave, Excel, and Word.
Windows 11’s strongest security defenses can be bypassed without a screwdriver
Researchers found a script-only attack, 'Download More RAM', that rewrites DIMM configuration chips to bypass Windows 11 VBS and HVCI security boundaries.
Researchers at the University of Birmingham and Durham University showed that overwriting configuration data on unprotected DDR4/DDR5 module chips creates memory aliases that let attackers with existing privileged access defeat Virtualisation-based Security and HVCI, re-enable blocklisted drivers, kill EDR, and bypass group policy. Microsoft assigned CVE-2026-23670 and shipped mitigations in its April 2026 updates; systems with Secure Boot enabled are protected. Affected unprotected product lines are estimated at more than half of the high-performance consumer memory market and over 70% of the gaming segment.