CVE-2022-49005 in Linux
Summary
by MITRE • 10/21/2024
In the Linux kernel, the following vulnerability has been resolved:
ASoC: ops: Fix bounds check for _sx controls
For _sx controls the semantics of the max field is not the usual one, max is the number of steps rather than the maximum value. This means that our check in snd_soc_put_volsw_sx() needs to just check against the maximum value.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 01/18/2026
The vulnerability CVE-2022-49005 addresses a critical bounds checking flaw in the Linux kernel's sound subsystem, specifically within the Advanced SoC (ASoC) framework that manages audio codec operations. This issue affects the handling of _sx controls, which are specialized audio volume controls used in embedded audio systems. The flaw exists in the snd_soc_put_volsw_sx() function where improper validation logic leads to potential security risks. The root cause stems from a misunderstanding of the semantic meaning of the max field parameter for _sx controls, which deviates from conventional expectations in audio control implementations.
The technical implementation flaw occurs when the kernel validates audio control values for _sx controls, where the max field represents the number of discrete steps rather than an upper numeric boundary. This semantic difference requires specialized validation logic that correctly interprets the step-based nature of these controls. The existing code performs incorrect bounds checking by treating the max field as a maximum numeric value rather than a step count, creating a potential pathway for invalid control values to bypass validation mechanisms. This misinterpretation allows for out-of-bounds operations that could lead to memory corruption or privilege escalation within the audio subsystem.
The operational impact of this vulnerability extends across various Linux-based embedded systems, mobile devices, and audio processing platforms that rely on the ASoC framework for audio codec management. Attackers could potentially exploit this flaw to manipulate audio controls in ways that might lead to system instability, unauthorized privilege escalation, or even complete system compromise. The vulnerability affects devices where audio controls are dynamically modified through user-space applications or kernel modules, particularly those implementing advanced audio processing capabilities. The flaw is especially concerning in automotive infotainment systems, IoT devices, and mobile platforms where audio subsystems are integral to overall system functionality and security.
Mitigation strategies for CVE-2022-49005 involve applying the official kernel patch that corrects the bounds checking logic in the snd_soc_put_volsw_sx() function to properly handle the step-based semantics of _sx controls. System administrators should prioritize updating to kernel versions containing the fix, particularly those released after the vulnerability disclosure. Additional protective measures include implementing proper input validation for audio control parameters, monitoring for unusual audio subsystem behavior, and maintaining regular kernel updates to address similar vulnerabilities. The fix aligns with established security practices for kernel subsystem validation and follows principles outlined in the Common Weakness Enumeration framework where improper validation of input parameters represents a fundamental security risk. This vulnerability demonstrates the importance of semantic understanding in security implementations and the potential consequences of incorrect assumptions about parameter meanings in kernel code.