Description
In the Linux kernel, the following vulnerability has been resolved: HID: mcp2221: prevent a buffer overflow in mcp_smbus_write() Smatch Warning: drivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() '&mcp->txbuf[5]' too small (59 vs 255) drivers/hid/hid-mcp2221.c:388 mcp_smbus_write() error: __memcpy() 'buf' too small (34 vs 255) The 'len' variable can take a value between 0-255 as it can come from data->block[0] and it is user data. So add an bound check to prevent a buffer overflow in memcpy().
Affected products
linux: linux kernel
References5
- git.kernel.org/stable/c/3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270 Patch
- git.kernel.org/stable/c/62ac2473553a00229e67bdf3cb023b62cf7f5a9a Patch
- git.kernel.org/stable/c/6402116a7b5ec80fa40fd145a80c813019cd555f Patch
- git.kernel.org/stable/c/66c8e816f2f2ca4a61b406503bd10bad1b35f72f Patch
- git.kernel.org/stable/c/91443c669d280937968f0aa4edefa741cfe35314 Patch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 13 · as of 7 November 2026
- CWE
- CWE-787
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