CVE-2018-5083 in K7
Summary
by MITRE
In K7 AntiVirus 15.1.0306, the driver file (K7FWHlpr.sys) allows local users to cause a denial of service (BSOD) or possibly have unspecified other impact because of not validating input values from IOCtl 0x8300215B.
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Analysis
by VulDB Data Team • 01/28/2021
The vulnerability identified as CVE-2018-5083 resides within the K7 AntiVirus 15.1.0306 security suite, specifically affecting the kernel-mode driver component known as K7FWHlpr.sys. This driver operates at the privileged system level and handles various input/output control operations through Windows Device I/O Control mechanisms. The flaw manifests when the driver processes IOCTL 0x8300215B requests without proper validation of input parameters, creating a dangerous condition where malicious or unintended input can trigger system instability. The vulnerability represents a classic example of insufficient input validation, a weakness that has been consistently documented across numerous security frameworks and standards. The driver's failure to validate user-supplied data before processing creates an attack surface that can be exploited by local adversaries to manipulate system behavior.
The technical implementation of this vulnerability stems from the driver's lack of parameter validation during IOCTL 0x8300215B handling. When a user-space application sends a malformed or specially crafted IOCTL request to the K7FWHlpr.sys driver, the kernel component fails to perform adequate checks on the input values before utilizing them in system operations. This absence of validation creates multiple potential paths for exploitation, including buffer overflows, memory corruption, or improper resource handling that can lead to system crashes. The vulnerability aligns with CWE-20, which describes "Improper Input Validation," and CWE-122, which addresses "Heap-based Buffer Overflow." The lack of proper bounds checking and parameter validation in kernel-mode drivers creates an environment where arbitrary code execution or system instability becomes possible, as demonstrated by the potential for blue screen of death (BSOD) conditions.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, presenting significant risks to system availability and potentially enabling more sophisticated attacks. Local users with minimal privileges can trigger system crashes that result in complete system shutdowns, forcing administrators to restart affected systems and potentially losing unsaved data. The unspecified other impacts mentioned in the vulnerability description suggest that beyond simple BSOD conditions, the vulnerability may enable privilege escalation or other security implications that could be leveraged by attackers. This type of vulnerability directly impacts the principle of least privilege and can undermine the security posture of systems running vulnerable versions of K7 AntiVirus. The attack vector is particularly concerning because it requires only local system access, making it accessible to users who may not have elevated privileges, and the impact can be severe enough to disrupt business operations.
Mitigation strategies for CVE-2018-5083 should focus on both immediate remediation and long-term security hardening approaches. The most effective immediate solution involves updating to a patched version of K7 AntiVirus that properly validates all IOCTL input parameters before processing. Organizations should implement comprehensive patch management procedures to ensure all systems running vulnerable software receive updates promptly. Additionally, system administrators should consider implementing kernel-mode driver whitelisting policies and monitoring for unusual IOCTL activity patterns that might indicate exploitation attempts. From an operational security perspective, this vulnerability highlights the importance of proper input validation in kernel-mode components and aligns with ATT&CK technique T1068, which covers 'Exploitation for Privilege Escalation.' Organizations should also consider implementing runtime application control measures and monitoring for suspicious driver behavior to detect potential exploitation attempts before they can cause significant damage. The vulnerability serves as a reminder of the critical importance of secure coding practices in system-level software components and the necessity of thorough security testing before deployment.