CVE-2025-68783

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

ALSA: usb-mixer: us16x08: validate meter packet indices

get_meter_levels_from_urb() parses the 64-byte meter packets sent by

the device and fills the per-channel arrays meter_level[],

comp_level[] and master_level[] in struct snd_us16x08_meter_store.

Currently the function derives the channel index directly from the

meter packet (MUB2(meter_urb, s) - 1) and uses it to index those

arrays without validating the range. If the packet contains a

negative or out-of-range channel number, the driver may write past

the end of these arrays.

Introduce a local channel variable and validate it before updating the

arrays. We reject negative indices, limit meter_level[] and

comp_level[] to SND_US16X08_MAX_CHANNELS, and guard master_level[]

updates with ARRAY_SIZE(master_level).

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References