CVE-2026-50450

What it actually does

CVE-2026-50450 is a local elevation-of-privilege vulnerability in the Windows Wireless Wide Area Network Service caused by improper synchronization of a shared resource during concurrent execution. A low-privileged authenticated attacker with local code execution can attempt to trigger a race condition in the WWAN service and cause privileged service logic to operate on attacker-influenced state. Successful exploitation can allow the attacker to cross a local privilege boundary and gain high-privilege execution, commonly equivalent to SYSTEM or another highly privileged Windows security context, resulting in full confidentiality, integrity, and availability impact on the affected host.

Why it matters to the business

An attacker who already has a foothold on an affected Windows workstation or server could use this flaw to turn limited local access into full control of the machine. That can enable credential theft, disabling of security tools, lateral movement, data tampering, ransomware staging, and persistence. The vulnerability is not currently listed in CISA KEV and exploit maturity is reported as none, but it affects multiple supported Windows desktop and server releases, so broad patch coverage should still be prioritized through normal monthly remediation cycles, especially on endpoints where untrusted users can log in or run code.

How an attack unfolds

Exploitation requires the attacker to already be authenticated and able to execute code locally on an affected Windows system. The attacker targets the Windows Wireless Wide Area Network Service, which runs with elevated privileges and manages mobile broadband/WWAN functionality. By repeatedly invoking service-accessible operations in carefully timed concurrent sequences, the attacker attempts to win a race condition involving improperly synchronized shared state. If successful, the service may perform a privileged operation using corrupted, stale, or attacker-controlled state. The attacker then leverages the resulting privilege boundary bypass to execute code with elevated rights, modify protected system settings, create persistence, dump credentials, or disable defenses. Because the attack complexity is high, exploitation is timing-sensitive and may require repeated attempts, service instability, or observable failures before success.

How to fix it

Apply the Microsoft security update that addresses CVE-2026-50450 for all affected Windows versions: Windows 10 1809, Windows 10 21H2, Windows 10 22H2, Windows 11 24H2, Windows 11 25H2, Windows 11 26H1, Windows Server 2019, Windows Server 2022, and Windows Server 2025. No fixed build numbers were provided in the input, so remediation should be verified against Microsoft’s official Security Update Guide, Windows Update, WSUS, Microsoft Configuration Manager, or the organization’s patch-management inventory. Where immediate patching is not possible, reduce exposure by limiting local interactive access, removing unnecessary local administrator rights, restricting execution from user-writable paths, enforcing application control, and disabling the Windows Wireless Wide Area Network Service only where WWAN/mobile broadband functionality is not required and after operational validation. Treat mitigations as temporary; patching is the primary fix.

How to confirm the fix worked

Confirm that each affected system has installed the Microsoft security update that supersedes this vulnerability for its Windows release. Validate through Windows Update history, WSUS/Configuration Manager compliance, Microsoft Defender Vulnerability Management, or equivalent endpoint inventory. On individual systems, confirm the OS build and installed cumulative update level with supported Windows management tooling, then compare it with Microsoft’s Security Update Guide for the relevant release. If WWAN is not required and was disabled as a mitigation, verify the WwanSvc service startup type and operational impact. Also validate that no unpatched or unsupported Windows builds remain in endpoint, server, VDI, lab, and golden-image inventories.

Typical attack path

1. Gain initial authenticated local access to an affected Windows workstation or server through phishing, stolen credentials, remote access abuse, or another vulnerability.
2. Confirm the target is running an affected Windows version with the Windows Wireless Wide Area Network Service present and unpatched.
3. Run a local exploit process that interacts with WWAN-related service interfaces or state transitions in parallel to trigger the race condition.
4. Repeat the race attempts until the service performs a privileged action using attacker-influenced or inconsistent shared state.
5. Obtain elevated execution, typically SYSTEM-level or equivalent high-integrity privileges.
6. Use the elevated context to dump credentials, disable endpoint defenses, install persistence, move laterally, or stage follow-on payloads such as ransomware.

How to detect it

There are no public, vulnerability-specific exploit indicators provided for this issue, and race-condition privilege escalation often leaves weak or indirect forensic evidence. Hunt for signs of local privilege escalation and post-exploitation on affected Windows systems. Useful log sources include Windows Security logs, System logs, Service Control Manager events, Windows Error Reporting, Sysmon or EDR telemetry, PowerShell logs, and Microsoft-Windows-WWAN-SVC event logs where available. Review for repeated crashes or restarts of the Windows Wireless Wide Area Network Service, unusual access to WWAN-related components by low-privileged processes, bursts of short-lived local processes followed by SYSTEM-level execution, unexpected services or scheduled tasks, local account creation, additions to privileged groups, credential dumping behavior, security tool tampering, and suspicious process ancestry involving svchost.exe hosting WwanSvc. Relevant Windows events include process creation events, special privilege assignment events, service installation events, local user/group modification events, logon events, and service failure events. Because successful exploitation would likely be followed by broader host compromise actions, correlate suspected WWAN service anomalies with downstream behaviors such as lsass.exe access, suspicious PowerShell, new autoruns, firewall changes, or lateral movement attempts.

• WwanSvc
• Windows Wireless Wide Area Network Service
• Microsoft-Windows-WWAN-SVC-Events
• svchost.exe -k LocalServiceNetworkRestricted
• Service Control Manager Event ID 7031
• Service Control Manager Event ID 7034
• Service Control Manager Event ID 7045
• Windows Error Reporting Event ID 1000
• Windows Error Reporting Event ID 1001
• Security Event ID 4672
• Security Event ID 4688
• Security Event ID 4720
• Security Event ID 4732
• Sysmon Event ID 1
• Sysmon Event ID 10
• lsass.exe

What your security team should do

• Prioritize patch deployment to Windows endpoints and servers that allow local user logon, shared use, developer activity, kiosk use, VDI access, or third-party application execution.
• Use centralized patch reporting to identify affected Windows 10, Windows 11, Windows Server 2019, Windows Server 2022, and Windows Server 2025 systems that have not received the relevant Microsoft security update.
• Harden local privilege boundaries by minimizing local administrator membership, enforcing least privilege, and monitoring for unexpected privilege escalation events.
• Increase monitoring for suspicious activity around WwanSvc, service crashes, unusual SYSTEM-level process creation, new service installation, new local users, and endpoint security tampering.
• Where WWAN/mobile broadband is not used, evaluate disabling the Windows Wireless Wide Area Network Service as a temporary compensating control until patching is complete.
• Because exploitation is local and high complexity with no known mature public exploit at the time of assessment, prioritize this behind remotely exploitable KEV vulnerabilities but ahead of low-impact local issues on high-risk user endpoints.