CVE-2021-3625: Zephyrproject Zephyr

Critical severity, CVSS 9.8. EPSS: 2.3% chance of exploitation in the next 30 days.

Buffer overflow in Zephyr USB DFU DNLOAD. Zephyr versions >= v2.5.0 contain Heap-based Buffer Overflow (CWE-122). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-c3gr-hgvr-f363

Affected products

• Zephyrproject Zephyr: from 2.5.0, before 2.7.0 (fixed in 2.7.0)

Published 2021-10-05. Last modified 2026-06-17.