# CVE-2026-42804

## Summary

- **CVE ID:** CVE-2026-42804
- **Severity:** HIGH
- **CVSS Score:** 7.6 (CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H)
- **CWE:** CWE-121
- **Published:** Sep 10, 2026
- **Last Modified:** Sep 10, 2026

## Description

A stack-based buffer overflow vulnerability exists in the Bosch Sensortec BHI360 SensorAPI(C-Library) in versions up to and including commit d6b200416a.

The vulnerability is located within the FIFO parsing and debug logging subsystem inside the function bhi360_parse_debug_message() in bhi360_parse.c (lines 1852-1875). 

The parser trusts the first payload byte of a debug frame as the message length (msg_length) and copies that many bytes into a fixed-size 17-byte stack buffer (debug_msg) via memcpy without performing any bounds checking.

A locally or physically positioned attacker (e.g., via a malicious sensor, counterfeit hardware module, or a Man-in-the-Middle on the communication bus) can exploit this vulnerability by injecting a crafted debug frame with a length byte exceeding 16.

This corrupts adjacent stack data, including the saved return address.

Furthermore, because the overflowed buffer is subsequently passed to a printf-style logging sink, the attacker can supply format string specifiers (e.g., %n) to execute arbitrary code on the host microcontroller/SoC or cause a reliable system crash (Denial of Service).

## Affected Products

- Bosch Sensortec — BHI360_SensorAPI (C-Library) (2.1.0)

## References

- [CNA](https://psirt.bosch.com/security-advisories/BOSCH-SA-223618.html)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.25%
- **EPSS Percentile:** 16.9

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-11._