CVE-2026-65681 in Windows
Summary
by MITRE • 08/12/2026
Null pointer dereference in Windows iSCSI Target Service allows an unauthorized attacker to deny service over a network.
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Analysis
by VulDB Data Team • 08/12/2026
A null pointer dereference vulnerability exists within the Windows iSCSI Target Service that enables unauthorized remote attackers to execute a denial of service attack against targeted systems. This flaw occurs when the iSCSI target service processes specific malformed network requests without proper validation of pointer references, leading to a scenario where the application attempts to access memory at address zero. The vulnerability resides in the service's handling of incoming iSCSI protocol commands and can be exploited by sending specially crafted packets to the iSCSI target port typically running on TCP port 3260. When the service encounters these malformed requests, it fails to validate that certain pointers are properly initialized before attempting to dereference them, resulting in a crash of the iSCSI target service process.
The technical implementation of this vulnerability demonstrates a classic null pointer dereference pattern that falls under CWE-476, which specifically addresses the use of null references in software applications. The operational impact extends beyond simple service disruption as attackers can repeatedly exploit this weakness to maintain persistent denial of service conditions against iSCSI target servers. This type of vulnerability represents a significant concern for enterprise environments that rely on iSCSI storage networks for critical data infrastructure, as it allows attackers with network access to destabilize storage services without requiring authentication credentials. The attack vector is particularly dangerous because it operates at the network level and can be executed from remote locations, making traditional network segmentation measures insufficient for protection.
From an adversarial perspective, this vulnerability aligns with ATT&CK technique T1499.004 which covers network denial of service attacks through exploitation of service vulnerabilities. The exploitability characteristics make this a preferred target for attackers seeking to disrupt storage infrastructure, as iSCSI targets often serve as critical components in enterprise data centers and cloud environments. Organizations utilizing iSCSI storage solutions face significant risk from this vulnerability since the attack can be executed without specialized privileges or credentials, making it accessible to threat actors with basic network reconnaissance capabilities. The service disruption caused by this exploit directly impacts business continuity and can lead to cascading failures in applications that depend on the affected storage resources.
Mitigation strategies should focus on immediate patch deployment through Microsoft's regular security updates, as well as implementing network-based controls such as firewall rules that restrict access to iSCSI target ports from trusted networks only. System administrators should consider disabling iSCSI target services if they are not actively required, and implement monitoring solutions to detect unusual patterns of connection attempts that may indicate exploitation attempts. Additionally, network segmentation approaches should be employed to isolate iSCSI services from general corporate networks, reducing the attack surface available to potential adversaries. The vulnerability highlights the importance of robust input validation in network service implementations and underscores the need for comprehensive security testing of critical infrastructure components within enterprise environments.