How severe is CVE-2023-42866?

CVE-2023-42866 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-42866 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-42866?

CVE-2023-42866 primarily affects Apple Safari. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-42866?

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.

Does CVE-2023-42866 have an EU (EUVD) identifier?

Yes. CVE-2023-42866 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-47287.

When was CVE-2023-42866 published?

CVE-2023-42866 was published on 2024-01-10 and last updated on 2026-06-17.

CVE-2023-42866

CVE-2023-42866 is a high-severity vulnerability in Apple Safari 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.

Key facts

Severity: High (CVSS 3.x base score 8.8)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-47287
Affected product: Apple Safari
Published: 2024-01-10
Last modified: 2026-06-17

Description

The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.5, iOS 16.6 and iPadOS 16.6, tvOS 16.6, Safari 16.6, watchOS 9.6. Processing web content may lead to arbitrary code execution.

Frequently asked questions

What is CVE-2023-42866?: The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.5, iOS 16.6 and iPadOS 16.6, tvOS 16.6, Safari 16.6, watchOS 9.6. Processing web content may lead to arbitrary code execution.
How severe is CVE-2023-42866?: CVE-2023-42866 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-42866 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-42866?: CVE-2023-42866 primarily affects Apple Safari. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-42866?: 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.
Does CVE-2023-42866 have an EU (EUVD) identifier?: Yes. CVE-2023-42866 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-47287.
When was CVE-2023-42866 published?: CVE-2023-42866 was published on 2024-01-10 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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