CVE-2025-50169 in Windows
Summary
by MITRE • 08/12/2025
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows SMB allows an unauthorized attacker to execute code over a network.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 11/22/2025
The vulnerability identified as CVE-2025-50169 represents a critical race condition flaw within the Windows Server Message Block protocol implementation that enables remote code execution through improper synchronization of shared resources. This vulnerability specifically affects the SMB protocol stack where concurrent access to shared resources occurs without adequate protective mechanisms, creating opportunities for malicious actors to exploit temporal inconsistencies in resource handling. The flaw resides in how the operating system manages simultaneous requests to shared network resources, allowing attackers to manipulate the timing of operations to achieve unauthorized code execution.
The technical root cause of this vulnerability aligns with CWE-367, which describes the improper handling of concurrent access to shared resources leading to race conditions. In the context of Windows SMB, the race condition manifests when multiple processes or threads attempt to access the same shared resource simultaneously without proper locking mechanisms or atomic operations. This allows an attacker to carefully time their network requests to exploit the window of opportunity between resource allocation and access validation, potentially leading to privilege escalation or arbitrary code execution on the target system. The vulnerability specifically impacts the SMB server implementation where shared file and printer resources are accessed concurrently by multiple clients.
Operationally, this vulnerability presents a significant threat to enterprise networks as it enables remote code execution without requiring authentication for the initial exploit attempt. Attackers can leverage this race condition to execute malicious code on vulnerable Windows systems that are running SMB services, potentially compromising entire network infrastructures. The attack surface includes any Windows system that exposes SMB shares to network traffic, making it particularly dangerous for organizations with extensive file sharing configurations. The remote nature of the exploit means that attackers can operate from outside the network perimeter, potentially bypassing traditional network segmentation controls. This vulnerability directly maps to ATT&CK technique T1077 which describes the exploitation of remote services, and T1059 which covers command and script interpretation.
Mitigation strategies for CVE-2025-50169 should prioritize immediate patch deployment from Microsoft as the primary defense mechanism, alongside network-level protections such as SMB protocol version restrictions and firewall rules that limit SMB port access. Organizations should implement network segmentation to isolate critical systems from general network access and disable SMBv1 if not required for legacy compatibility. Additional protective measures include monitoring for unusual SMB traffic patterns, implementing intrusion detection systems to detect potential exploitation attempts, and conducting regular vulnerability assessments to identify systems running vulnerable SMB implementations. The remediation process should also include disabling unnecessary SMB shares, implementing proper access controls, and maintaining updated security baselines that enforce secure SMB configurations. Organizations should also consider implementing endpoint detection and response solutions to identify potential exploitation attempts and establish incident response procedures specifically addressing SMB-based remote code execution vulnerabilities.