What is CVE-2025-9557?

CVE-2025-9557 is a high-severity vulnerability in Zephyrproject-Rtos Zephyr, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.6/10. Published 2025-11-26.

How severe is CVE-2025-9557?

High severity. CVSS v3 base score is 7.6 out of 10.

Buffer overflow in Zephyrproject-Rtos Zephyr

CVE-2025-9557

‭An out-of-bound write can lead to an arbitrary code execution. Even on devices with some form of memory protection, this can still lead to‬ ‭a crash and a resultant denial of service.‬

Vulnerability class: Buffer Overflow

EPSS: 0.002 (10.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.6 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H.

Affected products

Zephyrproject-rtos Zephyr

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

vulnerabilities@zephyrproject.org

Frequently asked questions

What is CVE-2025-9557?: CVE-2025-9557 is a high-severity vulnerability in Zephyrproject-Rtos Zephyr, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.6/10. Published 2025-11-26.
How severe is CVE-2025-9557?: High severity. CVSS v3 base score is 7.6 out of 10.