Type Confusion in 802154 ACK Frames Handling

published 2021-05-24 5y ago modified 2026-06-17 4mo ago also EUVD-2021-26651

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.8%; EPSS 0.8% chance of exploitation in 30 days, percentile 58%
public exploits: 0; none known

Type Confusion in 802154 ACK Frames Handling. Zephyr versions >= v2.4.0 contain NULL Pointer Dereference (CWE-476). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-27r3-rxch-2hm7

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Exploit prediction

0.85% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

zephyrproject-rtos zephyr

Classification

Weakness

CWE-476 NULL Pointer Dereference
CWE-843 Access of Resource Using Incompatible Type

References

github.com /zephyrproject-rtos/zephyr/security/advisories/GHSA-27r3-rxch-2hm7
third-party-advisory

Sources

CVE List CVE-2021-3320
NVD CVE-2021-3320

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