CVE-2026-83925 in Windows
Summary
by MITRE • 10/14/2026
Use of uninitialized resource in Windows Kernel allows an authorized attacker to disclose information locally.
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Analysis
by VulDB Data Team • 10/14/2026
The vulnerability described involves the use of an uninitialized resource within the Microsoft Windows kernel, a critical component of the operating system responsible for managing hardware and software resources at a low level. This specific flaw falls under the category of CWE-457, which is defined as the Use of Uninitialized Variable or Resource. In this context, the kernel fails to properly initialize certain memory structures or data fields before they are accessed by subsequent operations. When an authorized attacker interacts with these uninitialized resources, the system may return stale data from previous allocations rather than secure, randomized, or null values. This behavior creates a predictable information leak that can be exploited to reveal sensitive internal states of the operating system.
From a technical perspective, kernel memory is often reused across different processes and contexts without being fully cleared if initialization routines are bypassed or omitted due to logical errors in code paths. An attacker with local access can trigger specific API calls or driver interactions that cause the kernel to read from these uninitialized pointers or buffers. Because the content of this memory depends on prior allocations, it may contain cryptographic keys, session tokens, process identifiers, or other sensitive data previously held by another application or system component. The lack of proper initialization means there is no guarantee that the returned values are random or sanitized, allowing for deterministic exploitation where the attacker can reconstruct meaningful information about the host environment.
The operational impact of this vulnerability centers on local privilege escalation and information disclosure. While the initial description notes that an authorized attacker can disclose information locally, the implications extend beyond simple data leakage. Knowledge gained from reading uninitialized kernel memory can facilitate further attacks, such as bypassing security controls like Address Space Layout Randomization (ASLR) or identifying valid targets for subsequent exploitation attempts. This aligns with ATT&CK technique T1082, System Information Discovery, and potentially T1537, Transfer Data to Cloud Account if the disclosed data is exfiltrated externally. The severity of this issue lies in its potential to serve as a stepping stone for more severe compromises, including full system takeover or persistence mechanisms that rely on understanding kernel internals.
Mitigation strategies primarily involve applying vendor-supplied security patches that address the root cause within the Windows kernel codebase. Administrators should ensure that all systems are updated with the latest cumulative updates provided by Microsoft to close these gaps in memory management logic. Additionally, defense-in-depth measures such as enabling Kernel Patch Protection (PatchGuard) and enforcing strict driver signing requirements can help mitigate the risk of exploitation by preventing unauthorized or unsigned drivers from interacting with vulnerable kernel structures. For organizations relying on legacy systems where immediate patching is not feasible, network segmentation and limiting local user privileges to only those strictly necessary for business operations can reduce the attack surface available to potential adversaries seeking to exploit this flaw.