CVE-2020-9983

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-10-16 · updated 2026-06-17
Weakness: CWE-787

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.

Affected products

Apple iCloud for Windows: 11.5
Apple iPadOS: before 14.0 — fixed in 14.0
Apple Iphone Os: before 14.0 — fixed in 14.0
Apple iTunes for Windows: 12.10.9
Apple Safari: before 14.0 — fixed in 14.0
Apple tvOS: 14.0
Apple watchOS: 7.0
Fedoraproject Fedora: 32, 33

How to fix

Upgrade to a fixed version: Apple iPadOS 14.0; Apple Iphone Os 14.0; Apple Safari 14.0. Check the vendor advisory for mitigations.

References

http://seclists.org/fulldisclosure/2020/Nov/18
http://seclists.org/fulldisclosure/2020/Nov/19
http://seclists.org/fulldisclosure/2020/Nov/20
http://seclists.org/fulldisclosure/2020/Nov/22
http://www.openwall.com/lists/oss-security/2020/11/23/3
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BY2OBQZFMEFZOSWXPXHPEHOJXXILEEX2/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PDGBNKYT7NMW7CJ26YFUPUHPJVYGV7IQ/
https://security.gentoo.org/glsa/202012-10
https://support.apple.com/HT211845
https://support.apple.com/kb/HT211843
https://support.apple.com/kb/HT211844
https://support.apple.com/kb/HT211850

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