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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 · 1d agofirst · 1d agoAdvisory 3 sources1

Microsoft’s September 2026 Patch Tuesday addresses 964 CVEs (CVE-2026-81963, CVE-2026-85880)

Microsoft's September 2026 Patch Tuesday fixes a record 964 CVEs, including two zero-days actively exploited in the wild.

Microsoft patched a record 964 CVEs in its September 2026 Patch Tuesday release, with 101 rated critical and 824 rated important, making it the largest Patch Tuesday to date. The release includes fixes for two zero-days that were exploited in the wild, with CVE-2026-81963 and CVE-2026-85880 highlighted in the release. Affected products span Windows core components, Office, Exchange, .NET, Visual Studio, Active Directory services (including AD CS and AD FS) and numerous Azure services. Tenable notes the release surpasses July's as the biggest ever.

Tenable Blog · 8d agoVulnerability in the wildCVE-2026-81963CVE-2026-858801

ZDI-26-541: (Pwn2Own) Microsoft Windows win32kfull Use-After-Free Local Privilege Escalation Vulnerability

ZDI discloses a Pwn2Own Windows win32kfull use-after-free local privilege escalation flaw (CVE-2026-65775, CVSS 8.8) requiring existing low-privileged code execution.

ZDI advisory ZDI-26-541 describes a use-after-free in Microsoft Windows win32kfull that allows local attackers to escalate privileges. Exploitation requires the attacker to first execute low-privileged code on the target system. The flaw carries a CVSS score of 8.8 and is assigned CVE-2026-65775; it was demonstrated at Pwn2Own.

ZDI Published Advisories · Aug 11, 2026VulnerabilityCVE-2026-657751

ZDI-26-540: (Pwn2Own) Microsoft Windows win32kfull Use-After-Free Information Disclosure Vulnerability

ZDI discloses CVE-2026-65776, a Pwn2Own win32kfull use-after-free in Windows enabling local information disclosure, CVSS 6.5.

ZDI-26-540 describes a use-after-free vulnerability in Microsoft Windows win32kfull, demonstrated at Pwn2Own, that allows local attackers to disclose sensitive information. Exploitation requires the attacker to first execute low-privileged code on the target system. ZDI assigned a CVSS score of 6.5, tracked as CVE-2026-65776.

ZDI Published Advisories · Aug 11, 2026VulnerabilityCVE-2026-65776

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 · 8d agoAdvisory

Windows memory integrity switches on automatically for eligible devices in October 2026

Microsoft's Windows quality updates will automatically enable memory integrity and Virtualization-based Security on eligible devices starting October 2026.

Beginning in October 2026, Windows quality updates will automatically enable memory integrity on eligible devices and turn on Virtualization-based Security where it is not already running. Memory integrity restricts kernel-mode execution to trusted, signed code and drivers, blocking kernel compromise and rootkits. Microsoft said existing administrator decisions remain in effect, and readiness checks weigh hardware capability, compatibility, and performance. Memory integrity also underpins hotpatch updates that install without a reboot, so unprotected devices are excluded from that servicing model.

Help Net Security · 13d agoAdvisory

Windows BitLocker Flaw Lets Attackers Execute Code on Vulnerable Systems

Microsoft patched CVE-2026-69449, a heap-based buffer overflow in Windows BitLocker allowing privileged local attackers to execute code; no exploitation reported.

Microsoft disclosed CVE-2026-69449 on September 8, 2026, an Important-severity heap-based buffer overflow (CWE-122) in Windows BitLocker with a CVSS 3.1 base score of 6.7. The attack vector is local (AV:L) with high privileges required, so exploitation needs privileged local access rather than remote access over the internet. Microsoft, as assigned CNA, has not reported public exploitation, and administrators are urged to inventory BitLocker-enabled systems and apply updates. Interim mitigations include least-privilege access, limiting administrative rights, and monitoring for unexpected elevated process activity.

GBHackers · 7d agoVulnerabilityCVE-2026-694491

Windows BitLocker Vulnerability Allows Attackers to Execute Malicious Code Remotely

Microsoft patched CVE-2026-69449, a heap-based buffer overflow in Windows BitLocker enabling code execution, affecting Windows 10/11 and Server 2012-2025 in September 2026 updates.

Microsoft disclosed CVE-2026-69449, a heap-based buffer overflow in Windows BitLocker rated Important, which could allow an authorized attacker to execute arbitrary code locally, with possible in-network exploitation via arbitrary endpoint calls. Microsoft rates exploitation as Less Likely and there was no public disclosure or in-the-wild exploitation at release. The flaw affects Windows 10 (1607-22H2), Windows 11 (23H2-26H1), and Windows Server 2012 through 2025, including Server Core. Fixes shipped in the September 2026 Patch Tuesday cumulative updates via platform-specific KBs such as KB5124012 and KB5122871.

Microsoft patches 400+ vulnerabilities, one zero-day under attack (CVE-2026-68820)

Microsoft's August 2026 Patch Tuesday fixes 400+ vulnerabilities, including an actively exploited Windows zero-day (CVE-2026-68820) used by North Korean attackers.

Microsoft's August 2026 Patch Tuesday fixes over 400 vulnerabilities, including CVE-2026-68820, a use-after-free in the Windows Ancillary Function Driver exploited in the wild by North Korean actors deploying a kernel-mode rootkit in Operation Dream Job. Critical unauthenticated remote code execution flaws in Microsoft QUIC (CVE-2026-62815) and Windows DNS (CVE-2026-62878) were also patched, alongside a SharePoint RCE chain combining CVE-2026-63520 with CVE-2026-55040. Researcher Nightmare-Eclipse released ShieldBreak, a PoC bypassing the July RoguePlanet Microsoft Defender patch (CVE-2026-50656), confirmed working by Will Dormann on Windows 11.

Help Net Security · Aug 12, 2026Exploit / PoC in the wildCVE-2026-68820CVE-2026-62832CVE-2026-72971+6 CVEs

Windows 11 KB5124008 update breaks domain trust for some users

Microsoft is investigating Windows 11 KB5124008 breaking Active Directory domain trust, leaving some users unable to log in with valid credentials.

Administrators report the Windows 11 KB5124008 security update breaks the secure channel between domain-joined machines and Active Directory, causing login failures on Windows 11 25H2 systems after reboot. The failures are linked to the Machine Identity Isolation feature, which in enforcement mode moves machine account secrets into Credential Guard and removes the LSA copy; one admin saw 11 of roughly 256 devices affected. Workarounds include setting MachineIdentityIsolation to 0 and repairing the secure channel with Test-ComputerSecureChannel, though Microsoft has confirmed no root cause or official fix and warns disabling the feature can also break domain authentication.

BleepingComputer · 2h agoVulnerability

ZDI-26-537: (Pwn2Own) Microsoft Windows storport Integer Overflow Local Privilege Escalation Vulnerability

ZDI discloses a Pwn2Own Windows storport integer overflow local privilege escalation flaw (CVE-2026-65814, CVSS 8.8) requiring existing low-privileged code execution.

ZDI advisory ZDI-26-537 describes an integer overflow in the Microsoft Windows storport driver that allows local attackers to escalate privileges. Exploitation requires the attacker to first obtain the ability to execute low-privileged code on the target system. The vulnerability has a CVSS rating of 8.8 and is tracked as CVE-2026-65814; it originated from Pwn2Own.

ZDI Published Advisories · Aug 11, 2026VulnerabilityCVE-2026-658141

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 · 8d agoAdvisory in the wild

New Windows Defender ShieldCrash 0-Day Bypasses Microsoft Patch to Read Files as SYSTEM

Researcher's ShieldCrash PoC claims Microsoft Defender still allows arbitrary file reads as SYSTEM on patched Windows, bypassing the CVE-2026-69414 fix.

Researcher MSNightmare released the ShieldCrash proof of concept showing Microsoft Defender can allegedly be made to read arbitrary files with SYSTEM privileges on fully patched Windows systems, bypassing the September 2026 fix for ShieldBreak (CVE-2026-69414). Microsoft has not confirmed the bypass, and the new flaw has no CVE assignment yet. The PoC repository contains C++ project files, a Warden.dll library, and an EICAR test archive, suggesting interaction with Defender's malware-detection and file-handling workflow. Reading files as SYSTEM could expose configuration files, credentials, private keys, and other users' data, though it does not enable code execution.

Heap overflow in kernel driver due to missing size validation

Fortinet fixes a CVSS 7.3 heap overflow in the FortiClient Windows kernel driver enabling code execution via crafted DNS responses.

Fortinet PSIRT advisory FG-IR-26-156, revised 2026-08-12, describes a heap-based buffer overflow (CWE-120, buffer copy without checking input size) in the FortiClient Windows kernel driver, scored CVSSv3 7.3. An unauthenticated attacker positioned to alter or craft DNS responses for a targeted host could execute arbitrary code via malicious packets. No CVE identifier or exploitation status is provided in the advisory text, so administrators should check the full bulletin for affected versions and fixed releases.

Fortinet PSIRT · Aug 12, 2026Advisory

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 · 8d agoAdvisory in the wildCVE-2026-69805CVE-2026-58649CVE-2026-69806+27 CVEs1

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.

Help Net Security · Aug 17, 2026VulnerabilityCVE-2026-236701

Microsoft Releases Emergency Windows 11 Update Following Patch Tuesday Bugs

Microsoft issued emergency Windows 11 update KB5129195 to fix Patch Tuesday regressions and fully close the CVE-2026-62721 privilege escalation flaw.

Microsoft shipped out-of-band cumulative update KB5129195 for Windows 11 24H2 and 25H2 (builds 26100.9457 and 26200.9457) after the September 8 Patch Tuesday rollup, which addressed over 960 CVEs including two actively exploited flaws, broke Remote Desktop Services, Hyper-V Plan9 folder sharing, and USB audio. The emergency release also strengthens the incomplete fix for CVE-2026-62721, an elevation-of-privilege flaw in the Windows User-Mode Power Service that could let a local attacker gain SYSTEM privileges. Companion patches cover Windows 11 26H1, Windows 10, and Windows Server. Some USB Audio Class 1.0 and AMD Radeon graphics issues remain unresolved.

Cyber Security News · 15h agoVulnerability in the wildCVE-2026-62721

ZDI-26-639: Oracle VirtualBox VMSVGA Heap-based Buffer Overflow Local Privilege Escalation Vulnerability

ZDI disclosed a heap-based buffer overflow in Oracle VirtualBox's VMSVGA component (CVE-2026-71116) enabling local privilege escalation.

Zero Day Initiative published ZDI-26-639, a CVSS 7.5 heap-based buffer overflow in the VMSVGA component of Oracle VirtualBox. Local attackers who already execute high-privileged code on the guest system can leverage the flaw to escalate privileges on affected installations. The vulnerability is tracked as CVE-2026-71116. No exploitation is reported.

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 · 8d agoAdvisory

Microsoft Patches Record 974 Flaws, Including Two Exploited Windows Zero-Days

Microsoft's September Patch Tuesday fixed a record 974 flaws, including two Windows privilege-escalation zero-days actively exploited and added to CISA's KEV catalog.

Microsoft's September 2026 Patch Tuesday addressed a record 974 vulnerabilities (999 including 25 non-Microsoft CVEs), with over 110 rated critical; 723 affect Windows and 111 affect Office. Two Windows privilege-escalation zero-days are actively exploited: CVE-2026-85880, an ALPC heap-based buffer overflow, and CVE-2026-81963, an improper link resolution flaw in the Windows Update Stack, both allowing attackers to gain SYSTEM privileges. CISA added both flaws to its KEV catalog, giving federal civilian agencies until September 22, 2026 to apply fixes. Volexity, Proofpoint, MSTIC, and independent researchers were credited with the reports; notable additional fixes include network-reachable RCEs in Exchange, SharePoint, SQL Server, Remote Desktop Services, DNS, and DHCP.

The Hacker News · 7d agoExploit / PoC in the wildCVE-2026-85880CVE-2026-81963CVE-2026-55007+9 CVEs

BTR Reforged: Weaponizing Defender’s Remediation Driver as a Kernel Operation Primitive

Check Point shows attackers can abuse Microsoft Defender's signed remediation driver for arbitrary Ring 0 file and registry operations without exploiting any vulnerability.

Check Point Research presents BTR Reforged, a technique that repurposes Microsoft Defender's trusted remediation driver into an attacker-controlled kernel operation primitive. The signed driver can be instructed to execute arbitrary file and registry operations from Ring 0 without exploits, vulnerabilities, or memory corruption. The work demonstrates how trusted security components can be turned into attacker primitives, which is relevant for defenders assessing driver abuse risks.

Check Point Research · 27d agoResearch

11 Best Device Control & USB Security Tools Compared (2026): Features & Pricing

2026 comparison of 11 device control and USB security tools ranks CoSoSys Endpoint Protector first for cross-platform control and DLP.

An editorial scorecard evaluates eleven device control and removable-media security tools across granularity, content-aware DLP, cross-platform parity, encryption/shadowing, and value. CoSoSys Endpoint Protector (now part of Netwrix) leads at 4.60 for genuine Windows, macOS, and Linux parity, with Ivanti DeviceLock at 4.25 for the deepest Windows peripheral control and Safetica positioned for SMB and mid-market value. Enterprise content-aware DLP anchors include Symantec (Broadcom), Forcepoint, Digital Guardian (Fortra), and Trellix, with pricing almost always per endpoint.

GBHackersupdated · 13h agofirst · 5d agoIndustry 14 sources

ZDI-26-696: Linux Kernel NTFS3 Journal Heap-based Buffer Overflow Code Execution Vulnerability

ZDI-26-696: Linux Kernel NTFS3 journal heap-based buffer overflow (CVE-2026-72196, CVSS 8.8) enables local arbitrary code execution.

ZDI advisory ZDI-26-696 describes a heap-based buffer overflow in the Linux Kernel NTFS3 journal handling, tracked as CVE-2026-72196 with a CVSS score of 8.8. Exploitation requires the attacker to first execute low-privileged code on the target system. Successful exploitation allows local attackers to execute arbitrary code. No in-the-wild exploitation is mentioned.

BraZetsu Malware Turns Compromised Windows Hosts Into Criminal Marketplace Inventory

Group-IB details BraZetsu, a modular Python Windows malware that monetizes compromised-host access through the Infected Marketplace for initial access brokers.

Group-IB attributes BraZetsu to the Exilware threat actor, believed to be native Portuguese speakers targeting Iberian and Latin American e-commerce, financial, industrial, and law enforcement victims. The framework, first observed in early May 2026, uses generative AI for data triage and target prioritization, steals browser histories and digital certificates, and hunts Brazilian CNAB financial remittance files. Access to compromised hosts is sold on the Infected Marketplace from roughly $5.80, letting buyers remotely deploy secondary payloads over WebSocket-linked infrastructure. Some samples evaded detection on VirusTotal; delivery likely uses VBS loaders from a domain also used to distribute the Ousaban banking trojan.

The Hacker News · 13d agoMalware in the wild

MacOS 27 - First Boot, (Tue, Sep 15th)

SANS ISC documents the expected network traffic macOS 27 'Golden Gate' generates on first boot to help defenders baseline their networks.

Johannes Ullrich of SANS Internet Storm Center captured roughly 300 packets from a macOS 27 'Golden Gate' system before user login, covering DHCP, IPv6 duplicate address discovery, DNS, and TCP behavior. macOS 27 resolves hostnames like albert.apple.com (device activation, certificate-pinned), push messaging hosts, and ipv4only.arpa for NAT64 networks. The OS still uses a TCP window scale of 6, ECN, and random timestamps, with only four TCP connections observed during boot. The analysis provides a reference baseline for security teams monitoring Apple endpoints.

SANS Internet Storm Center · 1d agoResearch

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.

WireGuard-Linux Stack-Based Buffer Overflow in lsiio (Linux IIO Userspace Tool) Due to Unbounded fscanf

The Linux IIO userspace tool lsiio has a stack buffer overflow in find_type_by_name() caused by unbounded fscanf reads of oversized filesystem-backed attribute values.

A stack-based buffer overflow exists in the Linux Industrial I/O (IIO) userspace utility lsiio. In the find_type_by_name() function, the program reads an unbounded string from a filesystem-backed attribute into a fixed-size stack buffer using fscanf("%s", ...). A crafted or oversized attribute value causes a write beyond the bounds of the destination buffer. Despite the title's reference to WireGuard-Linux, the flaw described is in the IIO lsiio utility.

Full Disclosure · 12d agoVulnerability

DeepZero: Open-source hunting for vulnerable Windows drivers

DeepZero, a new open-source engine, automates discovery of exploitable Windows kernel drivers for BYOVD attacks using Ghidra, Semgrep, and an LLM.

DeepZero is a free, open-source Python pipeline orchestrator that automates hunting for exploitable Windows kernel drivers relevant to BYOVD (bring your own vulnerable driver) attacks. Its seven-stage YAML pipeline parses PE headers, filters for kernel-mode drivers with IOCTL surfaces, excludes drivers listed on loldrivers.io, then runs headless Ghidra decompilation, Semgrep scanning, and an LLM-based exploitability assessment. The maintainer reports multiple verified vulnerabilities in the Snappy Driver Installer corpus, some still in the disclosure process, and notes findings involving plug-and-play-created device objects may need physical hardware to confirm.

Help Net Security · 17h agoTools

Researcher Drops New Microsoft Defender PoC Showing ShieldBreak Patch Can Be Bypassed

Researcher Chaotic Eclipse released a PoC showing CVE-2026-69414's patch is bypassable, allowing arbitrary file reads as SYSTEM on current Windows.

The researcher known as Chaotic Eclipse published a proof-of-concept for a zero-day in Microsoft Defender, dubbed ShieldCrash, assessed as a patch bypass for ShieldBreak (CVE-2026-69414, CVSS 7.8). The PoC demonstrates an arbitrary file read as SYSTEM with the latest Windows installed, and all supported desktop versions are said to be impacted. Microsoft patched the original issue in Microsoft Malware Protection Engine 1.1.26080.3, which updates automatically. The same researcher recently released PoCs for flaws in CrowdStrike Falcon Sensor, Kaspersky, Avast Antivirus and NVIDIA.

The Hacker News · 7d agoExploit / PoCCVE-2026-694141