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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.

Cyber Security Newsupdated · 6d agofirst · 6d agoVulnerability 3 sourcesCVE-2026-69485

Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories

Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.

Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.

Remote Desktop Services Failures on Windows Servers Following September Update

September 2026 Patch Tuesday updates cause Windows Server 2019/2022/2025 RDS sessions to freeze, forcing administrators to roll back.

Cumulative updates KB5122876 (Windows Server 2019), KB5122882 (2022), and KB5122871 (2025) trigger Remote Desktop Services freezes hours after boot, with RDP connections hanging at 'Connecting…' and Event ID 20498 logged. Administrators trace the fault to an apparent deadlock in RDPSERVERBASE!WDLIB_Close during session teardown; only hard resets restore service and the issue recurs. The same September release patched roughly 973 vulnerabilities, including two actively exploited zero-days (CVE-2026-81963, CVE-2026-85880, both in CISA's KEV) and a critical RDS RCE, CVE-2026-69525 (CVSS 9.8). Workarounds include DISM-based removal of the update or an unofficial FeatureManagement registry key disabling the suspected audio-redirection code path; Microsoft has not yet confirmed the bug.

Cyber Security Newsupdated · 20h agofirst · 5d agoVulnerability in the wild 20 sourcesCVE-2026-81963CVE-2026-85880CVE-2026-69525+1 CVEs1

Microsoft Confirms Remote Desktop Services Might Stop Working Following Sept. 2026 Security Update

Microsoft's September 2026 Patch Tuesday updates (KB5124008) can break Remote Desktop Services, causing RDP failures and freezes across Windows clients and servers.

Microsoft confirmed its September 2026 security updates, including KB5124008 for Windows 11 24H2/25H2, introduced a reliability regression where RDP connections fail after several minutes and servers hang at the 'Please wait for the Remote Desktop Configuration' screen. MMC, RDS Licensing Diagnoser, File Explorer, and the Windows Update settings page may also stop responding. The issue affects Windows 10/11 clients and Windows Server 2012 through 2025; Microsoft marked it Mitigated on September 11 and is developing a permanent fix, with VM restart offered as a temporary workaround.

Cyber Security News · 1d agoAdvisory

ClearFake Deploys Crypto Stealer That Uses Vulnerable Driver to Kill EDR Security Tools

Cisco Talos details ClearFake's fake-CAPTCHA chain deploying ZigCryptoStealer with a BYOVD attack that kills EDR processes, observed at a Ukrainian government organization in April 2026.

ClearFake compromises websites, injects JavaScript via a malicious Cloudflare Worker, retrieves instructions from BNB Smart Chain contracts (EtherHiding), and presents a fake Google CAPTCHA that tricks Windows users into pasting a command that loads a remote library over WebDAV via rundll32. The crypto-stealer branch uses DLL side-loading with a signed Chrome component to launch ZigCryptoStealer, which hijacks clipboard cryptocurrency addresses, alongside a signed but vulnerable Windows driver used in a BYOVD attack to terminate EDR processes. A parallel branch delivers Amatera secondary payloads that install a hidden remote-access client providing operator desktop control, with Cisco Talos tracking the remote-loader activity as UAT-10820. Talos observed unusual remote library execution at a Ukrainian government organization in April 2026 and assesses the attacks are part of a broader theft operation rather than a single targeted campaign.

Cyber Security Newsupdated · 4d agofirst · 6d agoMalware in the wild 4 sources1

Microsoft’s Biggest Patch Tuesday: 974 CVEs, 2 Zero-Days and 20 Wormable Bugs

Microsoft's record September 2026 Patch Tuesday fixes 974 CVEs, including two exploited Windows privilege-escalation zero-days and 20 wormable bugs.

Microsoft's September 2026 Patch Tuesday fixes a record 974 CVEs, including two actively exploited zero-days: CVE-2026-85880, an ALPC heap buffer overflow, and CVE-2026-81963 in the Windows Update Stack, both CVSS 7.8 local privilege escalations. It also addresses an unauthenticated Exchange RCE (CVE-2026-55007) triggered by Visio attachment content indexing under memory pressure, an RDP use-after-free (CVE-2026-69525, CVSS 9.8), and 20 wormable flaws in DNS, DHCP, SMB, Active Directory, and other components. ZDI attributed the rising volume partly to AI-assisted vulnerability discovery, noting no corresponding spike in active exploits yet.

Security Affairs · 6d agoVulnerability in the wildCVE-2026-85880CVE-2026-81963CVE-2026-55007+3 CVEs1

Update Chrome now to protect against an actively exploited vulnerability

Google shipped Chrome 153.0.8010.36/.37 fixing 230 flaws including actively exploited V8 out-of-bounds write CVE-2026-87491 enabling sandboxed code execution.

Chrome stable channel updated to 153.0.8010.36/.37 for Windows and Mac and 153.0.8010.36 for Linux, including 230 security fixes. CVE-2026-87491 is an out-of-bounds write in Chrome's V8 JavaScript engine that a crafted HTML page can exploit to execute arbitrary code inside the browser sandbox; Google rates it medium severity, but it is confirmed as actively exploited. The update also fixes five Critical vulnerabilities, four of which were found in WebGL. Users should update via Settings > About Chrome and restart the browser.

Malwarebytes Labs · 5d agoExploit / PoC in the wild 2 sourcesCVE-2026-874911

Passkey-themed social engineering leads to identity and cloud compromise

Microsoft tracks ongoing cloud intrusions where passkey-themed helpdesk lures enable AiTM credential theft, MFA persistence, and SharePoint data theft.

Microsoft Security Research is tracking active cloud-based intrusions, observed since May 2026, that begin with helpdesk impersonation calls and SMS lures urging urgent passkey, MFA, or SSO updates. The lures lead to adversary-in-the-middle phishing or device-code authentication flows that capture credentials and session tokens or grant actor access, after which the actors add authentication methods, conduct Microsoft Graph reconnaissance, and download SharePoint and OneDrive content via REST APIs. Phishing domains embed victim organization names as subdomains (e.g., contoso.add-passkey[.]com), are often registered with Nicenic, and go operational within hours. Microsoft advises revoking sessions and removing unauthorized authentication methods for confirmed compromises.

Microsoft Security Blogupdated · 4d agofirst · 6d agoThreat actor in the wild 13 sources2

Top 10 Best Enterprise Browsers in 2026

2026 enterprise browser guide ranks Island first and notes Mammoth Cyber's wind-down plus corrections to standard vendor shortlists.

An editorial guide assesses ten enterprise browser options, ranking category creator Island first for last-mile DLP and BYOD controls, followed by Palo Alto's Talon browser as a Prisma Access/SASE surface and Google Chrome Enterprise Premium for DLP on already-deployed browsers. It corrects common lists, noting SlashNext is browser-adjacent phishing and BEC defense rather than a managed browser, and that Mammoth Cyber has wound down independent operations. Microsoft Edge for Business is positioned as effectively free policy depth for Microsoft 365 estates, with Menlo Security offering an isolation-plus-browser blend.

Cyber Security News · 4d agoIndustry1

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.