CVE-2026-54999 in Windows
Summary
by MITRE • 07/14/2026
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over an adjacent network.
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Analysis
by VulDB Data Team • 07/14/2026
This vulnerability represents a critical race condition flaw within the Windows TCP/IP stack that enables remote code execution through improper synchronization of shared resources during concurrent operations. The issue stems from insufficient protective mechanisms when multiple threads or processes attempt to access the same network resources simultaneously, creating temporal windows where malicious actors can exploit inconsistencies in resource management. The vulnerability specifically affects systems running Windows operating systems and becomes exploitable when an attacker has adjacent network access, typically within the same broadcast domain or through network segmentation bypasses that allow direct communication with target systems. The race condition manifests during TCP/IP protocol handling operations where shared kernel resources are accessed without adequate mutual exclusion controls, allowing attackers to manipulate memory states or resource pointers in ways that can lead to arbitrary code execution.
The technical exploitation of this vulnerability leverages the fundamental principle that concurrent access to shared resources without proper synchronization primitives creates opportunities for malicious interference. When multiple network operations occur simultaneously within the Windows TCP/IP implementation, the lack of adequate locking mechanisms means that an attacker can time their malicious packets or operations to coincide with critical resource access points. This temporal inconsistency allows for memory corruption scenarios where attacker-controlled data can overwrite critical system structures or function pointers, ultimately leading to code execution privileges. The vulnerability aligns with CWE-362 which specifically addresses race conditions in concurrent programming contexts and represents a classic example of improper synchronization in kernel-level network components. The attack vector requires only adjacent network access, making it particularly dangerous in environments where network segmentation is not properly enforced or when attackers can establish footholds through social engineering or physical access methods.
The operational impact of this vulnerability extends beyond simple remote code execution to encompass potential system compromise and lateral movement capabilities within affected networks. Once successfully exploited, attackers can gain elevated privileges on compromised systems, potentially leading to complete domain compromise if the targeted systems are domain controllers or servers with administrative access. The vulnerability affects multiple Windows versions including various releases of windows 10, windows server 2016, windows server 2019, and windows server 2022, making it particularly widespread across enterprise environments that have not yet applied relevant security patches. The attack surface is broad as the vulnerability exists in core TCP/IP functionality that is essential for virtually all network communications on Windows systems, meaning that any active network connection could potentially be exploited. Network-based attacks can occur without requiring authentication or specific user interaction, making detection and prevention particularly challenging.
Mitigation strategies for this vulnerability must address both immediate patch management requirements and longer-term architectural improvements to prevent similar race conditions in network protocol implementations. Microsoft has released security updates through windows update channels that address the synchronization issues within the TCP/IP stack, requiring organizations to apply these patches promptly to eliminate the vulnerability exposure. Network administrators should implement additional defensive measures including network segmentation, firewall rules that restrict unnecessary adjacent network access, and monitoring for unusual network traffic patterns that might indicate exploitation attempts. The implementation of proper intrusion detection systems with signature-based detection capabilities can help identify potential exploitation attempts targeting this specific vulnerability. Organizations should also consider implementing runtime protection mechanisms such as address space layout randomization, data execution prevention, and exploit mitigation technologies to reduce the effectiveness of exploitation attempts even if patches are not immediately applied. The ATT&CK framework categorizes this type of vulnerability under privilege escalation techniques and remote code execution tactics, emphasizing the need for layered defensive approaches that combine patch management with network monitoring and endpoint protection solutions.