CVE-2026-87702 in Windows
Summary
by MITRE • 10/14/2026
Integer overflow or wraparound in Windows Resource Management (MRM) allows an authorized attacker to elevate privileges locally.
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Analysis
by VulDB Data Team • 10/14/2026
The vulnerability identified as an integer overflow within the Microsoft Resource Manager, commonly referred to by its abbreviation MRM, represents a critical flaw in how the operating system handles memory allocation and resource tracking for specific subsystems. This component is responsible for managing resources such as power states, device connections, and other system-level assets that require precise accounting of allocated versus available capacity. The core technical issue stems from improper validation of arithmetic operations when calculating buffer sizes or array indices associated with these managed resources. When an attacker provides specially crafted input data containing values near the maximum limit of a signed integer type, the calculation wraps around to a small positive number rather than failing safely. This wraparound condition leads to the allocation of a significantly smaller memory buffer than intended by the application logic, creating a classic heap-based buffer overflow scenario where subsequent write operations exceed the bounds of the allocated space.
From an operational perspective, this flaw allows for local privilege escalation, meaning that any user account with basic access rights on the affected Windows system can exploit this condition to execute arbitrary code within the context of higher-privileged processes or even the kernel itself. The attacker typically achieves this by triggering the integer overflow during a resource management operation, such as connecting a peripheral device or modifying power settings, which causes the malformed data to be processed by privileged services. By carefully crafting the payload written into the undersized buffer, an attacker can overwrite adjacent memory structures, including function pointers or exception handling routines, thereby redirecting execution flow to malicious shellcode. This capability effectively bypasses standard user-mode security boundaries and grants the adversary full control over the system, enabling them to install malware, exfiltrate sensitive data, create new administrative accounts, or disable security monitoring tools without detection by typical endpoint protection mechanisms that rely on process isolation models.
The classification of this vulnerability aligns closely with CWE-190, which defines integer overflow or wraparound errors, and often intersects with CWE-787, an out-of-bounds write condition resulting from the miscalculated buffer size. In terms of offensive security frameworks like MITRE ATT&CK, this exploit path corresponds to techniques involving local privilege escalation through memory corruption, specifically falling under tactics related to persistence or defense evasion once initial access is established via other vectors such as phishing or network exploitation. The impact extends beyond simple system compromise; because Resource Management operates at a low level within the Windows architecture, successful exploitation can destabilize the entire operating environment, leading to denial of service conditions if the memory corruption triggers critical kernel faults before code execution completes.
Mitigation strategies for this vulnerability primarily rely on timely application of vendor-provided security patches that correct the arithmetic validation logic and enforce stricter bounds checking during resource allocation routines. System administrators should prioritize updating affected Windows versions as soon as official updates are released, ensuring that automatic update mechanisms are enabled to reduce exposure windows. Additionally, implementing strict least-privilege policies can limit the blast radius if an exploit is attempted; by restricting user accounts from interacting with sensitive hardware interfaces or power management APIs unless absolutely necessary, organizations can raise the barrier for attackers attempting to trigger this specific code path. Endpoint detection and response solutions should also be configured to monitor for anomalous memory allocation patterns and unexpected privilege changes associated with resource management services, providing an additional layer of defense against exploitation attempts that may evade signature-based antivirus detections.