CVE-2021-30869: Apple iOS, iPadOS, and macOS Type Confusion Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 3 Nov 2021, 71 days after the CVE record was published.

How likely is exploitation in the next 30 days?

4.1%

EPSS score, percentile 90.8 of all scored records

How severe?

7.8 High

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

CISA deadline 17 Nov 2021. Apply updates per vendor instructions.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• before 14.4
• before 11.2
• before 12.5
• before 2021

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

CISA due date for this action: 17 November 2021.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

• https://nvd.nist.gov/vuln/detail/CVE-2021-30869

Affected products and versions

As listed in the CVE record.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Apple iOS, iPadOS, and macOS contain a type confusion vulnerability in the XNU which may allow a malicious application to execute code with kernel privileges.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

• CISA added CVE-2021-30869 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Nov 2021.
• CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
• The due date CISA sets for the required action is 17 Nov 2021.
• The CVE record was published on 24 Aug 2021, 71 days before it was added to KEV.
• The CVE record carries a CVSS v3.1 base score of 7.8 (High), taken from CISA's enrichment of the record.
• FIRST's EPSS model puts the probability of exploitation in the next 30 days at 4.1% (percentile 90.8), as of 28 Oct 2026.
• CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

A type confusion issue was addressed with improved state handling. This issue is fixed in iOS 12.5.5, iOS 14.4 and iPadOS 14.4, macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, Security Update 2021-006 Catalina. A malicious application may be able to execute arbitrary code with kernel privileges. Apple is aware of reports that an exploit for this issue exists in the wild.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

• CWE-843: Access of Resource Using Incompatible Type ('Type Confusion')

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

References

• support.apple.com
• support.apple.com
• support.apple.com
• support.apple.com

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