CVE-2026-50306 in Windows
Summary
by MITRE • 07/14/2026
Use after free in Windows TCP/IP allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 07/14/2026
This vulnerability represents a critical use-after-free condition within the Windows TCP/IP stack that enables local privilege escalation for authenticated attackers. The flaw occurs when the system fails to properly validate memory references during network protocol processing, creating opportunities for malicious code execution. Such vulnerabilities typically arise from improper handling of dynamically allocated memory where objects are freed but pointers remain accessible, allowing subsequent operations to reference deallocated memory locations.
The technical implementation involves the Windows TCP/IP driver or kernel components that manage network connections and packet processing. When legitimate network operations occur, specific conditions can trigger memory deallocation while other system processes continue to reference those freed memory regions. This creates a scenario where an attacker can manipulate the memory layout through controlled network traffic or system calls to execute arbitrary code with elevated privileges. The vulnerability is classified under CWE-416 as use-after-free error and aligns with ATT&CK technique T1068 which covers local privilege escalation.
The operational impact of this vulnerability extends beyond simple privilege elevation, as it allows attackers who already possess legitimate user credentials to escalate their access from standard user level to system administrator or kernel-level privileges. This capability enables comprehensive system compromise including access to encrypted data, modification of critical system files, installation of persistent backdoors, and potential lateral movement within network environments. The local nature of the attack means that physical access or remote access via other initial compromise vectors is sufficient to exploit this vulnerability.
Mitigation strategies must address both immediate protection and long-term security posture improvements. Microsoft has released security updates that correct the memory management issues in the TCP/IP stack through proper reference counting and validation mechanisms. Organizations should implement comprehensive patch management protocols ensuring timely deployment of security updates across all Windows systems. Additional defensive measures include network segmentation to limit lateral movement, monitoring for unusual network activity patterns, and implementing least privilege access controls to minimize potential damage from successful exploitation attempts.