How severe is CVE-2020-9983?

CVE-2020-9983 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-2020-9983 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-9983?

CVE-2020-9983 primarily affects Apple Icloud. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-9983?

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-2020-9983 published?

CVE-2020-9983 was published on 2020-10-16 and last updated on 2026-06-17.

CVE-2020-9983

CVE-2020-9983 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-787.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Apple Icloud
Published: 2020-10-16
Last modified: 2026-06-17

Description

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in Safari 14.0. Processing maliciously crafted web content may lead to code execution.

Frequently asked questions

What is CVE-2020-9983?: An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in Safari 14.0. Processing maliciously crafted web content may lead to code execution.
How severe is CVE-2020-9983?: CVE-2020-9983 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-2020-9983 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-9983?: CVE-2020-9983 primarily affects Apple Icloud. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-9983?: 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-2020-9983 published?: CVE-2020-9983 was published on 2020-10-16 and last updated on 2026-06-17.

References

Affected products (9)

cpe:2.3:a:apple:icloud:11.5:*:*:*:*:windows:*:*
cpe:2.3:a:apple:itunes:12.10.9:*:*:*:*:windows:*:*
cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:14.0:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:7.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

More vulnerabilities in Apple Icloud

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CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
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