ZeroHour

CVE-2026-69525

mass

Use-After-Free RCE in Windows Remote Desktop Services

CVSS 3.1
9.8 critical
EPSS
1%p63
Published
()
Modified
AI analysis

CVE-2026-69525 is a use-after-free memory corruption flaw (CWE-416) in Windows Remote Desktop Services, rated critical at CVSS 9.8. Per the CVSS vector, a remote, unauthenticated attacker can reach the vulnerable code path over the network with no privileges and no user interaction, presumably by sending crafted input to the RDP/RDS service. Successful exploitation yields remote code execution with high impact on confidentiality, integrity, and availability. Any Windows system running Remote Desktop Services is affected, and organizations exposing RDP (TCP 3389) to the internet are the primary concern, since public scans show millions of such endpoints. There is no public proof-of-concept or CISA KEV listing yet, and EPSS estimates a ~1.1% (63rd percentile) chance of exploitation within 30 days; the fix shipped as part of Microsoft's record 974-CVE Patch Tuesday, which separately included two exploited Windows zero-days and 20 wormable bugs.

What to do: Apply Microsoft's security update for CVE-2026-69525 as soon as possible, prioritizing hosts with RDP (TCP 3389) reachable from untrusted networks. Until patched, restrict RDP exposure via firewall rules, VPN, or RD Gateway, and enable Network Level Authentication as a precaution. Inventory internet-facing systems for exposed RDP listeners and monitor for exploitation activity.

Affected
Microsoft Windows Remote Desktop Services
Estimated exposure
mass~3-4 million internet-exposed RDP endpoints (per public internet-wide scans); millions more reachable internally — Internet-wide scans such as Shodan have consistently shown on the order of millions of RDP (TCP/3389) endpoints, and Remote Desktop Services is present on essentially every Windows system with remote desktop access enabled.

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

Use after free in Windows Remote Desktop Services allows an unauthorized attacker to execute code over a network.

Vendors
microsoft
Products
windows 10 1607, windows 10 1809, windows 10 21h2, windows 10 22h2, windows 11 23h2, windows 11 24h2, windows 11 25h2, windows 11 26h1, windows server 2012, windows server 2016, windows server 2019, windows server 2022
Weakness
CWE-416
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

In the news

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

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 · 6d agoExploit / PoC in the wildCVE-2026-85880CVE-2026-81963CVE-2026-55007+9 CVEs

Microsoft Patches Record 974 Vulnerabilities, Including Two Exploited Zero-Days

Microsoft's September 2026 Patch Tuesday fixes a record 974 CVEs, including two Windows zero-days exploited in the wild for privilege escalation.

Microsoft patched 974 vulnerabilities, its largest Patch Tuesday ever, including CVE-2026-85880, a heap buffer overflow in Windows ALPC allowing AppContainer sandbox escape to System, and CVE-2026-81963, a link-following flaw in the Windows Update Stack enabling local privilege escalation. Both were exploited as zero-days before the patch. ZDI's Dustin Childs says 20 of the fixed flaws are wormable, enabling unauthenticated remote code execution. The release also covers 723 Windows flaws and 222 Office bugs, plus fixes in Exchange, SharePoint, SQL Server, Azure and Exchange Server RCE (CVE-2026-55007).

SecurityWeek · 7d agoExploit / PoC in the wildCVE-2026-85880CVE-2026-81963CVE-2026-55007+5 CVEs

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.