How severe is CVE-2020-3846?

CVE-2020-3846 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-2020-3846 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3846?

CVE-2020-3846 primarily affects Apple Icloud. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-3846?

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-2020-3846 published?

CVE-2020-3846 was published on 2020-02-27 and last updated on 2026-06-17.

CVE-2020-3846

CVE-2020-3846 is a high-severity vulnerability in Apple Icloud 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. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apple Icloud
Published: 2020-02-27
Last modified: 2026-06-17

Description

A buffer overflow was addressed with improved size validation. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2, iTunes for Windows 12.10.4, iCloud for Windows 11.0, iCloud for Windows 7.17. Processing maliciously crafted XML may lead to an unexpected application termination or arbitrary code execution.

Frequently asked questions

What is CVE-2020-3846?: A buffer overflow was addressed with improved size validation. This issue is fixed in iOS 13.3.1 and iPadOS 13.3.1, macOS Catalina 10.15.3, tvOS 13.3.1, watchOS 6.1.2, iTunes for Windows 12.10.4, iCloud for Windows 11.0, iCloud for Windows 7.17. Processing maliciously crafted XML may lead to an unexpected application termination or arbitrary code execution.
How severe is CVE-2020-3846?: CVE-2020-3846 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-2020-3846 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3846?: CVE-2020-3846 primarily affects Apple Icloud. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-3846?: 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-2020-3846 published?: CVE-2020-3846 was published on 2020-02-27 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:apple:icloud:*:*:*:*:*:windows:*:*
cpe:2.3:a:apple:itunes:*:*:*:*:*:windows:*:*
cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

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