CVE-2026-89621
kernel: HID: mcp2221: validate report size in mcp2221_raw_event()
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 11, 2026
Updated · September 29, 2026
Description
A flaw was found in the Linux kernel's HID (Human Interface Device) mcp2221 driver. A malicious USB device can exploit this vulnerability by sending a specially crafted, short HID report with an invalid size. This can cause the system to read past valid memory, leading to the disclosure of sensitive kernel memory to userspace through the I2C/SMBus read path. This information disclosure could potentially expose confidential system data.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-125 · Out-of-bounds Read