CVE-2026-83868 in Windows
Summary
by MITRE • 10/14/2026
Concurrent execution using shared resource with improper synchronization ('race condition') in Microsoft Bluetooth Driver allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 10/14/2026
The vulnerability described involves a race condition within the Microsoft Bluetooth driver, specifically arising from concurrent execution accessing a shared resource without proper synchronization mechanisms. This flaw represents a classic concurrency bug where multiple threads or processes attempt to access and modify shared data simultaneously, leading to unpredictable behavior due to the non-deterministic nature of thread scheduling in operating systems. In this specific context, the lack of atomic operations or locking primitives allows an attacker to manipulate the state of critical driver structures during narrow time windows between check-and-act sequences. This type of vulnerability is formally categorized under CWE-362, which defines concurrent execution using shared resource with improper synchronization as a race condition that can lead to unintended side effects such as data corruption, denial of service, or privilege escalation.
From an operational perspective, the impact of this flaw is significant because it enables local privilege escalation for authorized users who have access to the Bluetooth stack interface. An attacker exploiting this vulnerability would need to trigger specific sequences of Bluetooth-related API calls that interact with the vulnerable shared resource in a tightly timed manner. By carefully crafting these requests and potentially using multiple threads or processes to increase the probability of hitting the race window, an authenticated user can overwrite critical memory structures within the kernel space. This manipulation allows the attacker to gain higher-level permissions than originally granted, effectively bypassing standard access control mechanisms imposed by the operating system. The ability to escalate privileges from a low-privileged account to SYSTEM or administrator level compromises the integrity and confidentiality of the entire host system.
This vulnerability aligns with MITRE ATT&CK technique T1068, which covers Exploitation for Privilege Escalation, specifically within the context of exploiting software vulnerabilities in operating systems. The attack vector is classified as Local (T1059), requiring physical or logical access to the machine and valid credentials before exploitation can commence. While the requirement for authentication limits the immediate threat from remote attackers, it remains a critical risk for environments where users may have standard user privileges but are trusted with sensitive data or systems that should not be compromised by lower-level accounts. The presence of such flaws in core system drivers like Bluetooth highlights the complexity and security challenges inherent in maintaining large codebases with deep kernel integration.
Mitigation strategies primarily involve applying vendor-supplied patches that address the synchronization issues within the driver source code. These updates typically introduce proper locking mechanisms, such as mutexes or spinlocks, to ensure exclusive access to shared resources during critical operations. Additionally, implementing memory protection features like Kernel Address Space Layout Randomization (KASLR) and Data Execution Prevention (DEP) can mitigate the exploitation of this vulnerability by making it more difficult for attackers to predict memory addresses and execute arbitrary code in kernel space. System administrators should ensure that all operating system components are kept up to date with the latest security updates provided by Microsoft, as these patches directly resolve the underlying race condition logic flaws. Furthermore, enforcing strict least-privilege policies can reduce the blast radius if such a vulnerability were successfully exploited, limiting the potential damage an attacker could inflict even after achieving initial access.