How severe is CVE-2021-3322?

CVE-2021-3322 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3322 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3322?

CVE-2021-3322 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3322?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-3322 published?

CVE-2021-3322 was published on 2021-10-12 and last updated on 2026-06-17.

CVE-2021-3322

CVE-2021-3322 is a medium-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 3.3
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Zephyrproject Zephyr
Published: 2021-10-12
Last modified: 2026-06-17

Description

Unexpected Pointer Aliasing in IEEE 802154 Fragment Reassembly in Zephyr. Zephyr versions >= >=2.4.0 contain NULL Pointer Dereference (CWE-476). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p86r-gc4r-4mq3

Frequently asked questions

What is CVE-2021-3322?: Unexpected Pointer Aliasing in IEEE 802154 Fragment Reassembly in Zephyr. Zephyr versions >= >=2.4.0 contain NULL Pointer Dereference (CWE-476). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p86r-gc4r-4mq3
How severe is CVE-2021-3322?: CVE-2021-3322 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3322 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3322?: CVE-2021-3322 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3322?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3322 published?: CVE-2021-3322 was published on 2021-10-12 and last updated on 2026-06-17.

References

http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p86r-gc4r-4mq3

Affected products (1)

cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*

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