CVE-2026-102198 in Windows
Summary
by MITRE • 10/13/2026
Out-of-bounds read in Windows Remote Desktop Protocol allows an authorized attacker to disclose information over a network.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/14/2026
The vulnerability described constitutes a critical security flaw within the Microsoft Windows Remote Desktop Protocol, specifically manifesting as an out-of-bounds read condition. This type of memory corruption error occurs when software attempts to access data at a memory location that is outside the boundaries of the intended buffer or array structure. In the context of network protocols like RDP, such flaws typically arise during the parsing and processing of incoming packets where input validation mechanisms fail to adequately verify the length or bounds of specific fields before they are utilized by the application logic. An attacker who has already established an authorized connection to a vulnerable Windows system can exploit this discrepancy to trigger the erroneous memory access operation. The primary consequence of this exploitation is the disclosure of sensitive information from the server's memory space, which may include cryptographic keys, session tokens, or other confidential data structures that were not intended for external exposure.
From a technical perspective, out-of-bounds read vulnerabilities are categorized under CWE-125 in the Common Weakness Enumeration standard, which defines improper limitation of an array read within a buffer boundary. This classification highlights the failure to enforce strict bounds checking on memory access operations. The operational impact is significant because it allows for information leakage without requiring elevated privileges or code execution capabilities beyond what is already granted by the authorized session. While this vulnerability does not directly lead to remote code execution, the exposure of internal state data can facilitate further attacks such as credential theft, session hijacking, or bypassing additional security controls that rely on the secrecy of specific memory contents. The attacker leverages the legitimate authentication mechanism to gain access and then crafts maliciously formatted RDP packets that trigger the out-of-bounds read during protocol negotiation or message processing phases.
In terms of threat modeling and adversary behavior, this vulnerability aligns with techniques observed in advanced persistent threats where initial access is maintained through valid credentials followed by data staging and collection activities. It corresponds to ATT&CK technique T1005, which involves Data from Local System, specifically the sub-technique related to application data or memory dumps. The exploitation path relies on the attacker's ability to send specially crafted requests that cause the RDP service to read beyond allocated buffers, thereby leaking adjacent memory contents into the response stream or causing a crash if error handling is insufficient. This behavior underscores the importance of robust input validation and secure coding practices in network-facing services where untrusted data flows are frequent despite authentication requirements.
Mitigation strategies for this vulnerability primarily involve applying the latest security updates provided by Microsoft, which patch the underlying code logic to enforce proper bounds checking during RDP packet processing. Administrators should ensure that all Windows systems with Remote Desktop enabled are fully patched and up-to-date with cumulative security releases. Additionally, network-level authentication policies can be tightened to restrict access only to trusted IP ranges or through virtual private networks, reducing the attack surface available to potential adversaries. Implementing strict firewall rules that limit RDP traffic to authorized sources further diminishes the risk of exploitation by ensuring that even if a vulnerability exists, it cannot be reached from untrusted network segments. Regular auditing of system logs for unusual RDP activity patterns can also aid in early detection of attempted exploits before successful data exfiltration occurs.