How severe is CVE-2021-30827?

CVE-2021-30827 has a CVSS 3.x base score of 7.8, 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-2021-30827 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30827?

CVE-2021-30827 primarily affects Apple Mac Os X. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-30827?

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-2021-30827 published?

CVE-2021-30827 was published on 2021-10-19 and last updated on 2026-06-17.

CVE-2021-30827

CVE-2021-30827 is a high-severity vulnerability in Apple Mac Os X with a CVSS 3.x base score of 7.8. 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-281.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-281
Affected product: Apple Mac Os X
Published: 2021-10-19
Last modified: 2026-06-17

Description

A permissions issue existed. This issue was addressed with improved permission validation. This issue is fixed in Security Update 2021-005 Catalina, macOS Big Sur 11.6. A local attacker may be able to elevate their privileges.

Frequently asked questions

What is CVE-2021-30827?: A permissions issue existed. This issue was addressed with improved permission validation. This issue is fixed in Security Update 2021-005 Catalina, macOS Big Sur 11.6. A local attacker may be able to elevate their privileges.
How severe is CVE-2021-30827?: CVE-2021-30827 has a CVSS 3.x base score of 7.8, 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-2021-30827 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30827?: CVE-2021-30827 primarily affects Apple Mac Os X. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-30827?: 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-2021-30827 published?: CVE-2021-30827 was published on 2021-10-19 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:-:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-005:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2020-007:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-001:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-002:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:security_update_2021-003:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:10.15.7:supplemental_update:*:*:*:*:*:*
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*

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