How severe is CVE-2021-39230?

CVE-2021-39230 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-39230 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39230?

CVE-2021-39230 affects Butter Project Butter. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-39230?

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-2021-39230 published?

CVE-2021-39230 was published on 2021-09-21 and last updated on 2026-06-17.

CVE-2021-39230

CVE-2021-39230 is a high-severity vulnerability in Butter Project Butter with a CVSS 3.x base score of 8.8. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 5.0
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Butter Project Butter
Published: 2021-09-21
Last modified: 2026-06-17

Description

Butter is a system usability utility. Due to a kernel error the JPNS kernel is being discontinued. Affected users are recommend to update to the Trinity kernel. There are no workarounds.

Frequently asked questions

What is CVE-2021-39230?: Butter is a system usability utility. Due to a kernel error the JPNS kernel is being discontinued. Affected users are recommend to update to the Trinity kernel. There are no workarounds.
How severe is CVE-2021-39230?: CVE-2021-39230 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-39230 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39230?: CVE-2021-39230 affects Butter Project Butter. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-39230?: 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-2021-39230 published?: CVE-2021-39230 was published on 2021-09-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:butter_project:butter:*:*:*:*:*:*:*:*

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