CVE-2026-54991 in Windows
Summary
by MITRE • 07/14/2026
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows USB Print Driver allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 07/14/2026
This vulnerability represents a classic race condition flaw in the Windows USB print driver component that enables local privilege escalation through improper synchronization of shared resources during concurrent execution. The underlying issue occurs when multiple threads or processes attempt to access and modify shared system resources without proper locking mechanisms, creating opportunities for malicious code injection and unauthorized privilege elevation. This type of vulnerability falls under CWE-362 which specifically addresses race conditions in concurrent programming where improper synchronization leads to security implications.
The technical implementation involves the USB print driver's handling of shared kernel-mode resources during print job processing and device communication operations. When multiple print operations occur simultaneously or when legitimate print drivers interact with system resources in overlapping time windows, the lack of proper mutex or semaphore controls allows an attacker to manipulate the timing of resource access. This creates a window where malicious code can be injected into the privileged print driver context, effectively elevating the attacker's privileges from standard user level to SYSTEM level access.
From an operational perspective this vulnerability presents significant risk to Windows environments as it requires only local user authentication to exploit, making it particularly dangerous in multi-user systems or shared workstations. The attack vector typically involves a malicious process that carefully orchestrates timing delays and resource access patterns to trigger the race condition, often through specialized tools or scripts designed to exploit specific kernel-level timing windows. This vulnerability can be leveraged by attackers to establish persistent backdoors, extract sensitive system information, or deploy additional malware payloads without requiring network connectivity or external attack vectors.
Organizations should implement immediate mitigations including applying Microsoft security updates that address the specific race condition in USB print drivers, disabling unnecessary USB printing capabilities where possible, and implementing strict access controls for print services. The vulnerability aligns with ATT&CK technique T1068 which covers local privilege escalation through kernel exploits, and T1547 which addresses registry run keys and startup folder modifications that attackers often use to maintain persistence after successful exploitation. System administrators should also consider monitoring for unusual print driver behavior or unauthorized print job submissions as potential indicators of exploitation attempts, while maintaining current threat intelligence feeds to track related attack patterns in the wild.