CVE-2025-11156 is a vulnerability identified in the Netskope Client agent on Windows systems, specifically involving a NULL pointer dereference (CWE-476). The issue arises when a local user with administrator privileges improperly loads the Netskope driver as a generic kernel service. This improper loading triggers the NULL pointer dereference, causing the Windows operating system to crash with a Blue Screen of Death (BSOD). The vulnerability results in a denial of service (DoS) condition, rendering the affected machine temporarily unusable until rebooted. The flaw does not require user interaction but does require elevated privileges (administrator) to exploit, limiting the attack surface to insiders or compromised admin accounts. The CVSS 4.0 vector indicates local attack vector (AV:L), low attack complexity (AC:L), no privileges required for attack (PR:H means high privileges required), no user interaction (UI:N), and impacts availability with low scope and no impact on confidentiality or integrity. No patches or exploits are currently publicly available, but the vulnerability is published and should be addressed promptly. This vulnerability could be leveraged by malicious insiders or attackers who have already gained administrative access to disrupt operations by causing system crashes. The Netskope Client is widely used in enterprise environments for cloud security posture management and secure access, making this vulnerability relevant for organizations relying on this product for endpoint security.

The primary impact of CVE-2025-11156 is a denial of service condition on Windows endpoints running the vulnerable Netskope Client. For European organizations, this could disrupt critical business operations, especially in environments with high dependency on endpoint security agents for cloud access and data protection. The requirement for administrator privileges limits exploitation to insiders or attackers who have already escalated privileges, reducing the risk of widespread remote attacks. However, targeted attacks against privileged users could lead to repeated system crashes, impacting availability and potentially causing operational downtime. In sectors such as finance, healthcare, and critical infrastructure, where uptime and endpoint security are paramount, this vulnerability could degrade trust in security controls and complicate incident response. Additionally, organizations with strict compliance requirements may face challenges if system availability is compromised. The lack of known exploits currently reduces immediate risk, but the vulnerability remains a concern for insider threat scenarios and privilege escalation aftermaths.

To mitigate CVE-2025-11156, organizations should implement the following specific measures: 1) Restrict administrative privileges strictly to trusted personnel and enforce least privilege principles to reduce the risk of exploitation. 2) Monitor and audit the use of administrative accounts on endpoints running Netskope Client to detect suspicious activity or unauthorized driver loading attempts. 3) Apply any available patches or updates from Netskope as soon as they are released, as no patches are currently available. 4) Implement endpoint protection solutions that can detect and block abnormal kernel driver loading behaviors. 5) Use application whitelisting or driver signing enforcement policies to prevent unauthorized or improper driver loads. 6) Educate administrators about the risks of improper driver loading and ensure secure configuration of the Netskope Client. 7) Maintain robust incident response plans to quickly recover from potential DoS conditions caused by this vulnerability. 8) Consider network segmentation and isolation of critical systems to limit the impact of potential insider attacks exploiting this flaw.