How severe is CVE-2021-3581?

CVE-2021-3581 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over physical access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-3581 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3581?

CVE-2021-3581 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3581?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-3581 published?

CVE-2021-3581 was published on 2021-10-05 and last updated on 2026-06-17.

CVE-2021-3581

CVE-2021-3581 is a high-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 7.0. 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-1284.

Key facts

Severity: High (CVSS 3.x base score 7.0)
CVSS v2: 5.8
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1284
Affected product: Zephyrproject Zephyr
Published: 2021-10-05
Last modified: 2026-06-17

Description

Buffer Access with Incorrect Length Value in zephyr. Zephyr versions >= >=2.5.0 contain Buffer Access with Incorrect Length Value (CWE-805). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8q65-5gqf-fmw5

Frequently asked questions

What is CVE-2021-3581?: Buffer Access with Incorrect Length Value in zephyr. Zephyr versions >= >=2.5.0 contain Buffer Access with Incorrect Length Value (CWE-805). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8q65-5gqf-fmw5
How severe is CVE-2021-3581?: CVE-2021-3581 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over physical access with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-3581 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3581?: CVE-2021-3581 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3581?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-3581 published?: CVE-2021-3581 was published on 2021-10-05 and last updated on 2026-06-17.

References

http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-8q65-5gqf-fmw5

Affected products (1)

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

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