CVE-2025-59514 Overview
CVE-2025-59514 is a local privilege escalation vulnerability in the Microsoft Streaming Service. Improper privilege management [CWE-269] within the service allows an authorized local attacker to elevate privileges on affected Windows systems. Microsoft published the advisory on November 11, 2025 as part of its security update cycle.
The flaw affects a broad range of supported Windows client and server releases, spanning Windows 10, Windows 11, and Windows Server versions from 2008 through 2025. Successful exploitation yields high impact to confidentiality, integrity, and availability on the local host.
Critical Impact
An authenticated local user can abuse the Microsoft Streaming Service to elevate privileges and gain SYSTEM-level control on unpatched Windows endpoints and servers.
Affected Products
- Microsoft Windows 10 (versions 1607, 1809, 21H2, 22H2)
- Microsoft Windows 11 (versions 23H2, 24H2, 25H2)
- Microsoft Windows Server (2008, 2012, 2016, 2019, 2022, 2022 23H2, 2025)
Discovery Timeline
- 2025-11-11 - CVE-2025-59514 published to NVD and Microsoft security advisory released
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-59514
Vulnerability Analysis
The Microsoft Streaming Service (MSKSSRV) processes kernel-mode streaming requests from user-mode clients on Windows. CVE-2025-59514 is classified as improper privilege management [CWE-269], indicating the service performs privileged operations on behalf of a caller without adequately restricting the caller's authority.
An attacker who is already authenticated on the target system can interact with the vulnerable service to perform actions that should be limited to higher-privileged principals. This crosses the trust boundary between a standard user and SYSTEM, resulting in local privilege escalation.
The CVSS vector requires local access and low privileges, with no user interaction. That profile aligns with post-compromise scenarios where an attacker has already achieved code execution as a standard user and seeks to escalate for persistence, credential theft, or lateral movement.
Root Cause
The root cause is improper enforcement of privilege boundaries inside the Streaming Service component. Requests originating from a lower-privileged token are handled with insufficient authorization checks, letting the caller invoke privileged code paths or manipulate resources reserved for SYSTEM.
Attack Vector
The attack vector is local. An authenticated attacker executes code as a standard user, opens a handle to the Streaming Service device or endpoint, and issues crafted requests that trigger the privileged code path. The vulnerability requires no user interaction and no elevated starting privileges beyond a valid local session.
No public proof-of-concept exploit is available at the time of publication, and CISA has not listed this CVE in the Known Exploited Vulnerabilities catalog. See the Microsoft Security Update CVE-2025-59514 advisory for vendor detail.
Detection Methods for CVE-2025-59514
Indicators of Compromise
- Unexpected child processes spawned by svchost.exe hosting the Streaming Service or by processes interacting with \\.\MSKSSRV device objects.
- New SYSTEM-context processes originating from standard user sessions shortly after Streaming Service interaction.
- Creation of scheduled tasks, services, or persistence artifacts by accounts that lack administrative rights.
Detection Strategies
- Monitor for standard user tokens opening handles to kernel streaming device objects followed by token elevation events.
- Correlate Windows Security Event 4688 (process creation) with parent-child relationships that show user-context processes producing SYSTEM-context children.
- Baseline normal Streaming Service usage on servers where multimedia components are not expected, and alert on anomalous access.
Monitoring Recommendations
- Enable command-line auditing and Sysmon Event ID 1 across Windows endpoints and servers to capture privilege-escalation chains.
- Ingest endpoint telemetry into a centralized data lake or SIEM to correlate local escalation activity across the fleet.
- Track patch state for MSRC advisory CVE-2025-59514 across all Windows 10, Windows 11, and Windows Server hosts.
How to Mitigate CVE-2025-59514
Immediate Actions Required
- Apply the Microsoft security update referenced in the MSRC advisory for CVE-2025-59514 to all affected Windows versions.
- Prioritize patching multi-user systems, terminal servers, and developer workstations where local users can execute code.
- Audit local account membership and remove unnecessary interactive login rights on servers.
Patch Information
Microsoft released fixes for CVE-2025-59514 through the November 2025 security update cycle. Consult the Microsoft Security Update CVE-2025-59514 page for the specific KB article and update package matching each affected Windows build.
Workarounds
- No official vendor workaround is documented; applying the security update is the supported remediation.
- Restrict interactive and remote-interactive logon rights to reduce the population of authenticated users who can reach the local attack surface.
- Enforce application control policies such as Windows Defender Application Control or AppLocker to block untrusted binaries that could stage the exploit.
# Verify patch status for CVE-2025-59514 on Windows hosts
Get-HotFix | Sort-Object -Property InstalledOn -Descending | Select-Object -First 20
# Check current Windows build to confirm it maps to a patched release
[System.Environment]::OSVersion.Version
(Get-ItemProperty 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion').DisplayVersion
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
