CVE-2026-19184

HighCVSS 8.4

Published: 05/10/2026(UTC)Updated: 06/10/2026(UTC)Translated: 05/10/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.10%

1th percentile - higher than 1% of all known CVEs

Summary

The NXP GAU ADC driver (adc_mcux_gau_adc.c) incorrectly validates the caller-supplied buffer size: it compares bytes against the number of channels (samples) and then uses that byte count as the number of uint16_t slots. As a result, a buffer accepted as 'large enough' can be written up to twice its size in bytes, causing an out-of-bounds write for every sample past the buffer's midpoint.

Risk Assessment

On builds with CONFIG_USERSPACE=y and the GAU ADC driver (NXP RW61x), a user-mode thread with access to the ADC device can deliberately submit a half-sized buffer, causing the driver's work-queue handler (running in supervisor mode) to write ADC results past the buffer's end. This can lead to kernel memory corruption, a crash, or a userspace-to-kernel privilege escalation.

Recommendation

Apply the vendor fix (Zephyr RTOS) that uses the shared adc_sequence_validate_buffer() helper and correctly converts buffer size to slot count. If updating is not possible, restrict ADC device access to trusted applications and disable CONFIG_USERSPACE where feasible.

Related vulnerabilities

Original NVD description (English source)

The NXP GAU ADC driver (drivers/adc/adc_mcux_gau_adc.c) validated the caller-supplied sequence->buffer_size, which is expressed in bytes, against the number of active channels, which is a sample count. It then stored that byte count directly in data->results_length and used it in mcux_gau_adc_read_samples() as the number of uint16_t slots available. Because each conversion result occupies sizeof(uint16_t) bytes, a buffer that was accepted as "large enough" could be written with up to twice its size in bytes, so every sample past the buffer's midpoint was written out of bounds. adc_read() and adc_read_async() are Zephyr system calls. The syscall verifier in drivers/adc/adc_handlers.c only confirms that the caller owns buffer_size writable bytes (K_SYSCALL_MEMORY_WRITE); deciding whether that size is sufficient for the requested channels and extra_samplings is delegated entirely to the driver. On a build with CONFIG_USERSPACE=y, a user-mode thread that has been granted the ADC device object could therefore submit a deliberately half-sized buffer and cause the driver's work-queue handler — which runs in supervisor mode, outside the caller's MPU restrictions — to write ADC conversion results past the end of that buffer, at an address and for a length of the caller's choosing. The overrun is bounded by the requested sequence: with sequence->options->extra_samplings set, the sampling loop walks the buffer pointer forward across every sampling, so the total overrun can reach the full size of the supplied buffer (kilobytes for a large extra_samplings). The written words are 16-bit ADC conversion results, so the content is only partially attacker-influenced (via the selected analog input, gain and resolution), but the destination and length are fully controlled — sufficient for kernel memory corruption, a crash, or a userspace-to-kernel privilege escalation. Builds without CONFIG_USERSPACE, or on SoCs other than NXP RW61x with the GAU ADC node enabled, are not exposed to the privilege boundary; there the same defect only causes a silent overflow when the application itself passes an undersized buffer. The fix replaces the ad-hoc check with the shared adc_sequence_validate_buffer() helper (validating against num_channels * sizeof(uint16_t)), stores buffer_size / sizeof(uint16_t) in results_length, and corrects the loop bound to a post-decrement so exactly the available number of slots may be written.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS