ZeroHour

Source: BleepingComputer

7 stories in the last 30d

Microsoft confirms KB5002914 Excel update breaks copy and paste

Microsoft confirms KB5002914 Office security update silently breaks copy-paste, autofill, and formula dragging in Excel 2016 through 2024.

Microsoft confirmed the September 2026 KB5002914 security update breaks copy-and-paste, autofill, and formula dragging in Excel 2024, 2021, 2019, and 2016. Failures occur silently with no beep or error message, leaving the destination unmodified. Uninstalling KB5002914 via OfficeC2RClient or Oarpmany restores functionality while Microsoft investigates.

BleepingComputerupdated · 13h agofirst · 14h agoAdvisory 3 sources1

Microsoft releases emergency Windows updates to fix RDS failures

Microsoft released emergency out-of-band Windows updates fixing Remote Desktop Services failures and Hyper-V issues caused by September 2026 security patches.

Microsoft issued out-of-band updates on September 14, 2026 to fix Remote Desktop Services instability introduced by the September security updates, which caused RDP connection and sign-in failures and unresponsive servers. Updates include KB5129194 (Windows 11 26H1), KB5129195 (Windows 11 24H2/25H2), KB5129236 (Windows 10), KB5129235 (Windows Server 2025), and KB5129237 (Windows Server 2022). The Windows 11 updates also fix a Hyper-V Plan9 shared folder issue and some USB Audio Class 1.0 multichannel problems, though remaining USB audio issues await a fix. Admins had previously used Group Policy mitigations or uninstalled the security updates, which removed security protections.

BleepingComputerupdated · 14h agofirst · 1d agoAdvisory 3 sources1

Microsoft releases Windows 10 KB5122878 extended security update

Microsoft shipped Windows 10 ESU update KB5122878, delivering the record September 2026 Patch Tuesday fixes, including patches for two actively exploited zero-days.

Microsoft released KB5122878 for Windows 10 Enterprise LTSC and ESU customers, moving builds 19045/19044 to .7725 with security and bug fixes. The update carries this month's record September 2026 Patch Tuesday set, which fixed 966 Microsoft vulnerabilities including two actively exploited zero-day flaws. It also fixes BitLocker recovery-key prompts and Remote Desktop audio redirection, and updates Secure Boot certificate rollout and Morocco time zone data. Microsoft reports no known issues with the update.

BleepingComputer · 7d agoAdvisory in the wild

Microsoft September 2026 Patch Tuesday fixes 966 flaws, 2 zero-days

Microsoft's September 2026 Patch Tuesday fixes a record 966 flaws, including two Windows zero-days actively exploited to gain SYSTEM privileges.

Microsoft's September 2026 Patch Tuesday addresses a record 966 vulnerabilities, including 105 rated Critical, 81 of them remote code execution bugs. Two zero-days were actively exploited: a Windows Update Stack link-following flaw and a Windows ALPC heap-based buffer overflow, both allowing local elevation to SYSTEM privileges. The ALPC flaw was reported by Volexity and Proofpoint researchers, while the Update Stack flaw was credited to Romain Deperne and the Microsoft Threat Intelligence Centre. Microsoft shared no details on how the flaws were exploited in attacks.

BleepingComputer · 7d agoAdvisory in the wildCVE-2026-69805CVE-2026-58649CVE-2026-69806+27 CVEs1

Windows 11 cumulative updates KB5124008 & KB5122880 released

Microsoft shipped mandatory September 2026 Patch Tuesday cumulative updates KB5124008 and KB5122880 for Windows 11, fixing vulnerabilities and adding features.

Microsoft released Windows 11 KB5124008 (versions 25H2/24H2) and KB5122880 (23H2) cumulative updates containing the September 2026 Patch Tuesday security patches, described as covering 1,000 vulnerabilities discovered in previous months. The updates are mandatory and add features including movable and resizable taskbars, Start menu customization, a Windows Search option to hide Bing and Store web suggestions, and Administrator Protection, a just-in-time admin privilege feature that is off by default and configurable via Intune OMA-URI or Group Policy.

BleepingComputer · 7d agoAdvisory

August updates trigger 0xc0000409 errors on Windows Server 2016

Microsoft says the August 2026 security update causes recurring CompatTelRunner.exe 0xc0000409 crashes on Windows Server 2016 with Compatibility Appraiser enabled; no functional impact.

Microsoft confirmed a known issue in which the August 2026 Windows security update generates recurring Application Error events (Event ID 1000, exception code 0xc0000409) in CompatTelRunner.exe on Windows Server 2016. The issue affects physical and virtual machines, including VMware and Azure environments, and per Microsoft does not affect device functionality. A permanent fix is planned for a future update, and the event log entries can be dismissed temporarily.

BleepingComputer · 7d agoAdvisory

Microsoft: Windows Server 2025 changes causing app crashes

Microsoft warns Windows Server 2025 memory-management changes crash AWE apps, including SQL Server with Lock Pages in Memory; disable LPIM as workaround.

Microsoft confirmed a known issue where Windows Server 2025 memory-management changes cause access violations, memory corruption, or unexpected termination in applications using Address Windowing Extensions (AWE). SQL Server running with the Lock Pages in Memory (LPIM) policy is affected, with symptoms including 0xC0000005 access violations, DBCC CHECKDB failures, crash dumps, and services stopping or restarting unexpectedly. Microsoft's temporary workaround is to disable the LPIM policy for the SQL Server service account or disable AWE in other affected apps, with a permanent fix promised in a future Windows update.

BleepingComputer · 7d agoAdvisory1