CVE-2018-3971 in HitmanPro.Alert
Summary
by MITRE
An exploitable arbitrary write vulnerability exists in the 0x2222CC IOCTL handler functionality of Sophos HitmanPro.Alert 3.7.6.744. A specially crafted IRP request can cause the driver to write data under controlled by an attacker address, resulting in memory corruption. An attacker can send IRP request to trigger this vulnerability.
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Analysis
by VulDB Data Team • 06/03/2023
The vulnerability identified as CVE-2018-3971 represents a critical arbitrary write flaw within the Sophos HitmanPro.Alert driver component, specifically affecting version 3.7.6.744. This issue manifests in the 0x2222CC IOCTL handler functionality, which serves as a communication interface between user-mode applications and kernel-mode driver components. The vulnerability arises from insufficient input validation and memory management within the driver's IOCTL processing logic, creating a pathway for malicious actors to manipulate kernel memory through carefully crafted infrared pulse requests.
The technical exploitation of this vulnerability occurs through the manipulation of Input/Output Control (IRP) requests, which are fundamental components of the Windows kernel's device I/O subsystem. When an attacker submits a specially crafted IRP request containing malicious data structures, the driver fails to properly validate the target memory addresses or data lengths, allowing arbitrary data to be written to locations controlled by the attacker. This flaw directly maps to CWE-787: Out-of-bounds Write, which specifically addresses buffer overflow conditions that can result in arbitrary code execution or system compromise. The vulnerability's impact is amplified by the fact that kernel-mode drivers operate with the highest privilege levels in Windows systems, providing attackers with direct access to system memory and potential escalation to full system compromise.
The operational implications of this vulnerability extend beyond simple memory corruption, as it enables attackers to manipulate critical system components through the kernel driver interface. Attackers can leverage this arbitrary write capability to overwrite function pointers, modify process control blocks, or inject malicious code into protected memory regions, effectively bypassing standard security mechanisms such as DEP (Data Execution Prevention) and ASLR (Address Space Layout Randomization). The attack vector requires minimal privileges since the vulnerability exists within a kernel driver that typically runs with SYSTEM level privileges, making it particularly dangerous for endpoint security solutions that are designed to protect against such threats. This vulnerability directly aligns with ATT&CK technique T1068: Exploitation for Privilege Escalation, as it provides a pathway for attackers to elevate their privileges from standard user level to kernel level access.
Mitigation strategies for CVE-2018-3971 should focus on immediate patching of the Sophos HitmanPro.Alert software to the latest version that addresses the IOCTL handler validation issues. Organizations should implement strict driver signature enforcement policies and disable unnecessary kernel-mode drivers to reduce attack surface. Additionally, monitoring for suspicious IRP requests and implementing kernel-mode protection mechanisms such as Control Flow Guard (CFG) can help detect and prevent exploitation attempts. The vulnerability highlights the critical importance of proper input validation in kernel-mode components and serves as a reminder that security controls must be implemented at all levels of the system architecture, particularly in components that interface directly with the operating system kernel.