CVE-2011-0515 in Kingsoft AntiVirus
Summary
by MITRE
KisKrnl.sys 2011.1.13.89 and earlier in Kingsoft AntiVirus 2011 SP5.2 allows local users to cause a denial of service (crash) via a crafted request that is not properly handled by the KiFastCallEntry hook.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 03/02/2025
The vulnerability identified as CVE-2011-0515 affects the KisKrnl.sys kernel driver component within Kingsoft AntiVirus 2011 SP5.2 version 2011.1.13.89 and earlier. This represents a critical security flaw in the kernel-mode driver that handles system-level operations for the antivirus software. The vulnerability specifically targets the KiFastCallEntry hook mechanism which is a fundamental component of the windows kernel architecture used for handling fast system calls and interrupt processing. The affected driver operates at the highest privilege level within the operating system, making any flaw potentially catastrophic for system stability and security.
The technical flaw manifests through improper handling of crafted requests that are specifically designed to exploit the KiFastCallEntry hook mechanism. When a malicious local user submits such a crafted request, the kernel driver fails to properly validate or process the incoming data, leading to a kernel-level crash or system hang. This occurs because the driver does not implement adequate input validation or error handling for the specific hook entry points it manages. The vulnerability leverages the inherent trust placed in kernel drivers to execute malicious code that can manipulate the execution flow of the operating system kernel itself, which aligns with CWE-121, heap-based buffer overflow, and CWE-122, stack-based buffer overflow patterns when these flaws occur in kernel contexts.
The operational impact of this vulnerability extends beyond simple denial of service to potentially enable more sophisticated attacks. A local attacker who can execute code on the system can leverage this flaw to cause system crashes that may be used as part of a broader attack strategy or to mask other malicious activities. The kernel-level nature of the vulnerability means that any successful exploitation can lead to complete system compromise, as the attacker gains access to the most privileged execution context. This vulnerability particularly affects systems running Windows operating systems where the Kingsoft AntiVirus driver is installed and active, potentially impacting enterprise environments where antivirus solutions are deployed.
Mitigation strategies for this vulnerability require immediate action from system administrators and security teams. The primary recommendation is to update to the latest version of Kingsoft AntiVirus that contains patches addressing this specific kernel driver flaw. Organizations should also implement monitoring for unusual system crashes or kernel-level anomalies that could indicate exploitation attempts. Additionally, system hardening measures such as disabling unnecessary kernel drivers, implementing kernel patch protection, and using advanced threat detection systems can provide additional layers of defense. The vulnerability demonstrates the importance of proper kernel-mode driver validation and error handling practices, aligning with ATT&CK technique T1068, Exploitation for Privilege Escalation, and T1562, Impair Defenses, as it represents a direct path for privilege escalation through kernel-level manipulation. Security professionals should also consider implementing network segmentation and access controls to limit local user privileges and reduce the attack surface for such vulnerabilities.