How severe is CVE-2021-1829?

CVE-2021-1829 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1829 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1829?

CVE-2021-1829 affects Apple Macos. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1829?

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

When was CVE-2021-1829 published?

CVE-2021-1829 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-1829

CVE-2021-1829 is a critical-severity vulnerability in Apple Macos with a CVSS 3.x base score of 9.8. 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-843.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-843
Affected product: Apple Macos
Published: 2021-09-08
Last modified: 2026-06-17

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.3. An application may be able to execute arbitrary code with kernel privileges.

Frequently asked questions

What is CVE-2021-1829?: A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.3. An application may be able to execute arbitrary code with kernel privileges.
How severe is CVE-2021-1829?: CVE-2021-1829 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1829 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1829?: CVE-2021-1829 affects Apple Macos. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1829?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-1829 published?: CVE-2021-1829 was published on 2021-09-08 and last updated on 2026-06-17.

References

https://support.apple.com/en-us/HT212325

Affected products (1)

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

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