CVE-2024-55414 in SM56 Modem WDM Driver
Summary
by MITRE • 01/07/2025
A vulnerability exits in driver SmSerl64.sys in Motorola SM56 Modem WDM Driver v6.12.23.0, which allows low-privileged users to mapping physical memory via specially crafted IOCTL requests . This can be exploited for privilege escalation, code execution under high privileges, and information disclosure. These signed drivers can also be used to bypass the Microsoft driver-signing policy to deploy malicious code.
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Analysis
by VulDB Data Team • 03/03/2026
The vulnerability identified as CVE-2024-55414 resides within the Motorola SM56 Modem WDM Driver version 6.12.23.0, specifically in the SmSerl64.sys driver component. This represents a critical security flaw that undermines the fundamental security boundaries of Windows operating systems by allowing unauthorized access to physical memory mapping capabilities. The issue manifests through improper input validation within the driver's IOCTL handling mechanism, creating a pathway for privilege escalation attacks that can be exploited by low-privileged users to gain elevated system access. The vulnerability falls under CWE-122, which describes improper restriction of operations within a memory buffer, and specifically relates to memory corruption vulnerabilities that enable arbitrary code execution through driver-level access.
The technical exploitation of this vulnerability occurs through specially crafted IOCTL (Input/Output Control) requests that manipulate the driver's memory mapping functions. When processed by the vulnerable SmSerl64.sys driver, these requests allow attackers to map physical memory addresses directly into the kernel space, bypassing normal memory protection mechanisms. This memory mapping capability enables attackers to read arbitrary memory locations, write to protected memory regions, and ultimately execute code with kernel-level privileges. The attack vector leverages the fact that the driver operates with high privileges and does not properly validate the memory addresses provided in the IOCTL parameters, creating a direct pathway for privilege escalation from user-level to kernel-level execution.
The operational impact of this vulnerability extends beyond simple privilege escalation to include comprehensive system compromise and information disclosure capabilities. Attackers can leverage the physical memory mapping to extract sensitive information from kernel memory, including credentials, encryption keys, and other confidential data stored in protected memory regions. The ability to execute code with kernel privileges enables attackers to establish persistent backdoors, modify system binaries, disable security features, and deploy additional malicious payloads. This vulnerability particularly affects systems running Windows operating systems where the Motorola SM56 modem driver is installed, potentially creating a widespread attack surface across enterprise networks and individual user machines.
The exploitation of this vulnerability also enables attackers to bypass Microsoft's driver-signing policies, which are fundamental security controls designed to prevent the execution of unsigned or malicious drivers. Since the vulnerable driver is digitally signed, attackers can use it as a foothold to deploy additional malicious code that may be unsigned or improperly signed, effectively circumventing the security protections that normally prevent unauthorized driver installation. This capability aligns with ATT&CK technique T1547.001, which describes the use of kernel drivers for privilege escalation and persistence. Organizations should consider this vulnerability as part of a broader attack chain that can lead to complete system compromise, including potential lateral movement and data exfiltration activities. Mitigation strategies should include immediate driver removal, system hardening measures, and enhanced monitoring for suspicious driver activity.
This vulnerability demonstrates the critical importance of proper input validation and memory management in kernel-mode drivers, as even signed drivers can pose significant security risks when they contain improper access controls or memory handling flaws. The attack surface created by such vulnerabilities extends to all systems where the affected driver is present, making it essential for security teams to conduct comprehensive inventory assessments and implement immediate remediation measures. The vulnerability also highlights the need for continuous driver security assessments and the importance of maintaining up-to-date driver versions from manufacturers to prevent exploitation of known security flaws. Organizations should implement network monitoring solutions to detect unauthorized driver installations and suspicious IOCTL activity patterns that may indicate exploitation attempts.