CVE-2007-1591 in Norton AntiVirus
Summary
by MITRE
VsapiNT.sys in the Scan Engine 8.0 for Trend Micro AntiVirus 14.10.1041, and other products, allows remote attackers to cause a denial of service (kernel fault and system crash) via a crafted UPX file with a certain field that triggers a divide-by-zero error.
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Analysis
by VulDB Data Team • 06/09/2025
The vulnerability identified as CVE-2007-1591 represents a critical kernel-level flaw within the Trend Micro AntiVirus Scan Engine 8.0 implementation, specifically affecting the VsapiNT.sys kernel driver. This vulnerability exists in the processing logic for UPX compressed executable files, where the driver fails to properly validate input parameters before performing arithmetic operations. The flaw manifests when a specially crafted UPX file contains a particular field value that triggers a divide-by-zero condition within the kernel space, leading to an unhandled exception that results in system instability and complete crash. The vulnerability demonstrates a classic lack of input validation and error handling in kernel-mode components, which directly violates fundamental security principles for operating system integrity.
The technical exploitation of this vulnerability occurs through the manipulation of UPX file format headers, specifically targeting a field that gets processed during decompression operations within the Trend Micro anti-virus engine. When the kernel driver encounters this malformed field value, it attempts to perform a division operation with zero as the divisor, causing an arithmetic exception that cannot be properly handled within the kernel context. This divide-by-zero error propagates through the kernel execution environment, ultimately resulting in a kernel fault that forces the operating system to crash and reboot. The vulnerability affects systems running Trend Micro AntiVirus versions 14.10.1041 and related products, where the VsapiNT.sys driver is actively processing executable files through the scan engine functionality.
The operational impact of this vulnerability extends beyond simple denial of service, as it represents a potential vector for system compromise and availability disruption in enterprise environments. Organizations relying on Trend Micro protection may experience unexpected system crashes, particularly when processing untrusted executable files or when encountering maliciously crafted UPX packed malware. The kernel-level nature of the flaw means that successful exploitation can lead to complete system instability, potentially allowing attackers to disrupt critical business operations or create opportunities for further exploitation. This vulnerability directly maps to CWE-369, which describes the weakness of dividing by zero in kernel mode code, and aligns with ATT&CK technique T1499.004 for network denial of service attacks through system resource exhaustion or kernel exploitation.
Mitigation strategies for CVE-2007-1591 should prioritize immediate patch deployment from Trend Micro, as the vendor has released updates addressing the divide-by-zero condition in the VsapiNT.sys driver. Organizations should also implement network segmentation and file validation policies to prevent processing of untrusted UPX files until patches are applied. System administrators should consider disabling automatic scanning of executable files from untrusted sources and implement additional monitoring for kernel-level exceptions. The vulnerability highlights the importance of proper error handling in kernel-mode drivers and underscores the necessity of comprehensive input validation across all system components. Security teams should also consider implementing behavioral monitoring to detect anomalous kernel activity that might indicate exploitation attempts, while ensuring that all anti-virus and security software components are regularly updated to address known vulnerabilities in their kernel drivers and system integration modules.