What is CVE-2021-3430?

CVE-2021-3430 is a medium-severity vulnerability in Zephyrproject Zephyr, classified under Reachable Assertion. CVSS score: 6.5/10. Published 2022-06-28.

How severe is CVE-2021-3430?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Is CVE-2021-3430 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Zephyrproject Zephyr

CVE-2021-3430

Assertion reachable with repeated LL_CONNECTION_PARAM_REQ. Zephyr versions >= v1.14 contain Reachable Assertion (CWE-617). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-46h3-hjcq-2jjr

Published 2022-06-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.009 (57.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 57.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: +0.000

Affected products

Zephyrproject Zephyr
Zephyrproject-Rtos Zephyr — versions v1.14.0, v2.5.0

Weakness classification (CWE)

CWE-617 — Reachable Assertion

Public proof-of-concept exploits

asset-group/vakt-ble-defender

References

github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-46h3-hjcq-2jjr (Third Party Advisory)

Frequently asked questions

What is CVE-2021-3430?: CVE-2021-3430 is a medium-severity vulnerability in Zephyrproject Zephyr, classified under Reachable Assertion. CVSS score: 6.5/10. Published 2022-06-28.
How severe is CVE-2021-3430?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-3430 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.