CVE-2026-43380

Technical Description

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

hwmon: (pmbus/q54sj108a2) fix stack overflow in debugfs read

The q54sj108a2_debugfs_read function suffers from a stack buffer overflow

due to incorrect arguments passed to bin2hex(). The function currently

passes 'data' as the destination and 'data_char' as the source.

Because bin2hex() converts each input byte into two hex characters, a

32-byte block read results in 64 bytes of output. Since 'data' is only

34 bytes (I2C_SMBUS_BLOCK_MAX + 2), this writes 30 bytes past the end

of the buffer onto the stack.

Additionally, the arguments were swapped: it was reading from the

zero-initialized 'data_char' and writing to 'data', resulting in

all-zero output regardless of the actual I2C read.

Fix this by:

1. Expanding 'data_char' to 66 bytes to safely hold the hex output.

2. Correcting the bin2hex() argument order and using the actual read count.

3. Using a pointer to select the correct output buffer for the final

simpl

Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. 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.

Affected Products

References