CVE-2026-89622

Public on 2026-09-11
Modified on 2026-09-15
Description
In the Linux kernel, the following vulnerability has been resolved:

HID: mcp2221: clear rxbuf after I2C/SMBus transfer completes

mcp_i2c_smbus_read() stores the caller-supplied buffer pointer in
mcp->rxbuf for the duration of a transfer but never clears it when the
transfer finishes or times out. Once the caller frees or reuses the
buffer, mcp->rxbuf becomes a dangling pointer. A delayed or spurious
MCP2221_I2C_GET_DATA report can then drive mcp2221_raw_event() to
memcpy device data into the freed memory, causing a write
use-after-free.

Route all return paths through a single exit point that clears
mcp->rxbuf and mcp->rxbuf_size, so that the existing !mcp->rxbuf guard
in the raw_event handler can reject any report arriving after the
transfer has ended.
Severity
Important severity
Important
See what this means
CVSS v3 Base Score
7.0
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 2 - Core kernel Not Affected
Amazon Linux 2 - Kernel-5.10 Extra kernel Not Affected
Amazon Linux 2 - Kernel-5.15 Extra kernel Not Affected
Amazon Linux 2 - Kernel-5.4 Extra kernel Not Affected
Amazon Linux 2023 kernel Not Affected
Amazon Linux 2023 kernel6.12 Not Affected
Amazon Linux 2023 kernel6.18 Not Affected

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 7.0 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H