CVE-2026-42804

HIGH
Published Sep 10, 2026 Modified Sep 10, 2026 CWE-121

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).

Is your site exposed to CVE-2026-42804?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.6
HIGH
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0025
Probability of exploitation
0.17%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-121 CWE-121

References

Frequently Asked Questions

What is CVE-2026-42804? +
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). It has a CVSS v3.1 base score of 7.6 (HIGH).
How severe is CVE-2026-42804? +
CVE-2026-42804 has a CVSS v3.1 score of 7.6 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-42804? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-42804 — free, no signup required.