medium · CVSS v3 5.5

CVE-2026-98678

A Linux kernel iio ADC driver for the AD4030 had an input validation flaw that allowed zero or negative oversampling ratios to be processed,

Overview

A Linux kernel iio ADC driver for the AD4030 had an input validation flaw that allowed zero or negative oversampling ratios to be processed, potentially causing undefined behavior. The issue was fixed by validating the value before computing its logarithm. This matters because it could lead to kernel instability or incorrect ADC data on affected systems.

Description

In the Linux kernel, the following vulnerability has been resolved: iio: adc: ad4030: fix invalid oversampling_ratio validation In ad4030_set_avg_frame_len(), the logarithm is calculated before input validation. Passing zero or negative values leads to an undefined result from ilog2(). Validate that the input is strictly positive prior to computing its logarithm.

Impact

The flaw can lead to kernel instability or denial of service by causing an undefined result from ilog2() when an attacker supplies zero or negative oversampling ratios. Systems that use the AD4030 ADC in the Linux kernel, such as embedded controllers, industrial equipment, and IoT devices, are at risk. Defenders should be aware that the vulnerability could disrupt data integrity and availability.

Remediation

Apply the kernel patch that validates oversampling_ratio > 0 before computing ilog2(). Update to a kernel version that includes the fix. If an update is not possible, disable the AD4030 driver or enforce strict input checks in firmware. Monitor for abnormal ADC behavior.

Risk context

The CVSS v3 score of 5.5 indicates medium risk, and no EPSS data is available. The vulnerability is not immediately exploitable without a valid oversampling_ratio input, so the urgency is moderate. Defenders should prioritize patching in environments where the AD4030 ADC is used.

Affected products

  • Linux kernel
  • AD4030 ADC driver
  • iio:adc:ad4030
  • Linux kernel iio subsystem
  • Linux kernel iio driver
  • AD4030
  • Linux kernel driver

Scores

Severity
medium
CVSS v2
4.9
CVSS v3
5.5
CVSS v4
—
EPSS
—

Linux kernel iio adc AD4030 oversampling validation medium denial-of-service

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