CVE-2025-40269
Description
A flaw was found in the ALSA USB audio driver of the Linux kernel. This vulnerability, a buffer overflow, occurs when the size of the Pulse-Code Modulation (PCM) stream data packets exceeds the maximum allowed by the USB descriptor. A local attacker could exploit this by providing specially crafted USB audio device parameters, causing the PCM transfer buffer to overflow. This could lead to sensitive information disclosure and potentially result in a denial of service (DoS).
Mitigation
To mitigate this issue, prevent the `snd_usb_audio` kernel module from loading if USB audio functionality is not required. Create a file `/etc/modprobe.d/disable-snd-usb-audio.conf` with the following content:
`install snd_usb_audio /bin/true`
After creating the file, a system reboot is required for the changes to take effect. This action will disable all USB audio device functionality.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.3 | N/A | 7.8 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | Low | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H
cve.org: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Integrity,Availability,Confidentiality
Technical Impact: DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands; Read Memory; Modify Memory
If the incorrect calculation is used in the context of memory allocation, then the software may create a buffer that is smaller or larger than expected. If the allocated buffer is smaller than expected, this could lead to an out-of-bounds read or write (CWE-119), possibly causing a crash, allowing arbitrary code execution, or exposing sensitive data.
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