How severe is CVE-2021-30668?

CVE-2021-30668 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-30668 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30668?

CVE-2021-30668 affects Apple Macos. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-30668?

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

When was CVE-2021-30668 published?

CVE-2021-30668 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-30668

CVE-2021-30668 is a medium-severity vulnerability in Apple Macos with a CVSS 3.x base score of 4.6. 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-287.

Key facts

Severity: Medium (CVSS 3.x base score 4.6)
CVSS v2: 2.1
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Apple Macos
Published: 2021-09-08
Last modified: 2026-06-17

Description

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.4. A person with physical access to a Mac may be able to bypass Login Window during a software update.

Frequently asked questions

What is CVE-2021-30668?: This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.4. A person with physical access to a Mac may be able to bypass Login Window during a software update.
How severe is CVE-2021-30668?: CVE-2021-30668 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over physical access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-30668 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30668?: CVE-2021-30668 affects Apple Macos. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-30668?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-30668 published?: CVE-2021-30668 was published on 2021-09-08 and last updated on 2026-06-17.

References

https://support.apple.com/en-us/HT212529

Affected products (1)

cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*

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