CVE-2026-63908: Input: atmel_mxt_ts - fix boundary check in mxt_prepare_cfg_mem

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-19 · updated 2026-10-30
Weakness: CWE-835

Description

In the Linux kernel, the following vulnerability has been resolved: Input: atmel_mxt_ts - fix boundary check in mxt_prepare_cfg_mem When a configuration file provides an object size that is larger than the driver's known mxt_obj_size(object), the driver intends to discard the extra bytes. The loop iterates using for (i = 0; i < size; i++). Inside the loop, the condition to skip processing extra bytes is: if (i > mxt_obj_size(object)) continue; Since i is a 0-based index, the valid indices for the object are 0 through mxt_obj_size(object) - 1. When i == mxt_obj_size(object), the condition evaluates to false, and the code processes the byte instead of discarding it. This causes the code to calculate byte_offset = reg + i - cfg->start_ofs and writes the byte there, overwriting exactly one byte of the adjacent instance or object. Update the boundary check to skip extra bytes correctly by using >=.

Affected products

Linux kernel: from 3.17 before 5.10.259; from 5.11 before 5.15.210; from 5.16 before 6.1.176; from 6.2 before 6.6.143; from 6.7 before 6.12.93; from 6.13 before 6.18.35 — fixed in 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.93, 6.18.35
Linux kernel: 3.17 — fixed in 7.1

How to fix

Upgrade to a fixed version: Linux kernel 5.10.259, 5.15.210, 6.1.176, 6.6.143; Linux kernel 7.1. Check the vendor advisory for mitigations.

References

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