How severe is CVE-2021-33889?

CVE-2021-33889 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33889 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33889?

CVE-2021-33889 affects Openthread Wpantund. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-33889?

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

When was CVE-2021-33889 published?

CVE-2021-33889 was published on 2021-07-02 and last updated on 2026-06-17.

CVE-2021-33889

CVE-2021-33889 is a medium-severity vulnerability in Openthread Wpantund with a CVSS 3.x base score of 6.8. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Openthread Wpantund
Published: 2021-07-02
Last modified: 2026-06-17

Description

OpenThread wpantund through 2021-07-02 has a stack-based Buffer Overflow because of an inconsistency in the integer data type for metric_len.

Frequently asked questions

What is CVE-2021-33889?: OpenThread wpantund through 2021-07-02 has a stack-based Buffer Overflow because of an inconsistency in the integer data type for metric_len.
How severe is CVE-2021-33889?: CVE-2021-33889 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33889 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33889?: CVE-2021-33889 affects Openthread Wpantund. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-33889?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33889 published?: CVE-2021-33889 was published on 2021-07-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:openthread:wpantund:*:*:*:*:*:*:*:*

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