CRITICAL

CVE-2021-3625

CVSS v3

9.8

CRITICAL

EPSS Score

2.3 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2021-3625 yet.

Full record on NVD

Description

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

Technical details

Published: 2021-10-05

Frequently asked questions

What is CVE-2021-3625?

Is CVE-2021-3625 actively exploited?

Active exploitation of CVE-2021-3625 has not been confirmed. Its EPSS score was 2.3% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-3625?

CVE-2021-3625 has a CVSS v3 base score of 9.8 (CRITICAL severity).

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