CVE-2025-59196 Overview
CVE-2025-59196 is a race condition vulnerability in the Windows Simple Service Discovery Protocol (SSDP) Service. The flaw allows an authorized local attacker to elevate privileges on affected Windows systems by exploiting improper synchronization of shared resources [CWE-362]. Microsoft addressed the issue in its October 2025 security update cycle.
The vulnerability affects a broad range of Windows client and server operating systems, spanning Windows 10, Windows 11, and Windows Server versions from 2008 through 2025. Successful exploitation grants elevated privileges, enabling attackers to compromise confidentiality, integrity, and availability on the local system.
Critical Impact
A local attacker with low-privilege access can win a race condition in the SSDP Service to gain elevated privileges, resulting in full compromise of the affected Windows host.
Affected Products
- Microsoft Windows 10 (1507, 1607, 1809, 21H2, 22H2)
- Microsoft Windows 11 (22H2, 23H2, 24H2, 25H2)
- Microsoft Windows Server 2008, 2012, 2016, 2019, 2022, 2022 23H2, and 2025
Discovery Timeline
- 2025-10-14 - CVE-2025-59196 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-59196
Vulnerability Analysis
The Windows SSDP Service (SSDPSRV) implements the discovery half of Universal Plug and Play (UPnP). It runs as a system-level service and manages device discovery messages on the local network. The flaw stems from concurrent access to a shared resource without adequate synchronization, creating a race window that a local attacker can exploit.
Exploitation requires local access with low privileges and no user interaction. The attack complexity is high because the attacker must reliably win the race, which depends on precise timing between competing threads. When exploited successfully, the attacker gains elevated privileges on the host and can execute code in a higher-privileged context.
Root Cause
The root cause is improper synchronization of shared resources within the SSDP Service [CWE-362]. Two or more execution paths access or modify the same object without correct locking, allowing an attacker to manipulate state between a check and its subsequent use. Race conditions of this type frequently manifest as time-of-check to time-of-use (TOCTOU) issues that permit privilege boundary violations.
Attack Vector
The attack vector is local. An authenticated user runs code that concurrently interacts with the SSDP Service, triggering the race window. By repeatedly invoking the affected code path and manipulating shared state, the attacker corrupts service context and elevates privileges. Microsoft has not disclosed a public proof-of-concept, and no exploit is currently available. See the Microsoft Security Update CVE-2025-59196 advisory for vendor details.
Detection Methods for CVE-2025-59196
Indicators of Compromise
- Unexpected child processes spawned by svchost.exe hosting the SSDP Service (SSDPSRV)
- Repeated, rapid start/stop or reconfiguration events on the SSDP Service from non-administrative accounts
- New privileged token assignments or process creations shortly after SSDP-related activity in event logs
Detection Strategies
- Hunt for local processes making high-frequency IOCTL or RPC calls into the SSDP Service from low-privilege sessions
- Correlate Windows Event ID 4688 (process creation) with parent svchost.exe -k LocalService running SSDP to identify anomalous child processes
- Baseline normal SSDP Service behavior and alert on deviations such as unexpected thread creation or handle duplication attempts
Monitoring Recommendations
- Enable Sysmon process and thread creation logging for services hosted under svchost.exe
- Forward SSDP-related service and security events to a centralized analytics platform for behavioral analysis
- Monitor for privilege escalation patterns following interactive logon by standard users
How to Mitigate CVE-2025-59196
Immediate Actions Required
- Apply the October 2025 Microsoft security updates addressing CVE-2025-59196 to all affected Windows client and server systems
- Prioritize patching on multi-user systems, terminal servers, and virtual desktop infrastructure where local users are present
- Audit local user privileges and remove unnecessary interactive logon rights on servers
Patch Information
Microsoft released a security update on October 14, 2025 that addresses CVE-2025-59196. Refer to the Microsoft Security Update CVE-2025-59196 advisory for the specific KB articles applicable to each supported Windows version and Server release.
Workarounds
- Disable the SSDP Discovery service (SSDPSRV) on systems that do not require UPnP device discovery, following organizational change control procedures
- Restrict local logon rights to trusted administrators on servers where SSDP cannot be disabled
- Apply application allowlisting to prevent execution of untrusted binaries from standard user contexts
# Disable SSDP Discovery service on systems that do not need UPnP
sc.exe config SSDPSRV start= disabled
sc.exe stop SSDPSRV
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
