CVE-2020-9866

CriticalCVSS 9.8/10Last modified Jun 17, 2026

Description

A buffer overflow was addressed with improved bounds checking. This issue is fixed in macOS Catalina 10.15.6, Security Update 2020-004 Mojave, Security Update 2020-004 High Sierra. A buffer overflow may result in arbitrary code execution.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-120

Affected software

No affected versions have been published.

Timeline

Published
Oct 27, 2020
Last modified
Jun 17, 2026
NVD status
Modified

Related CVEs from 2020

CVE-2020-98689.1A certificate validation issue existed when processing administrator added certificates. This issue was addressed with improved certificate CVE-2020-98697.5A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Catalina 10.15.6. A remote attacker may CVE-2020-98708.8A logic issue was addressed with improved validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6, tvOS 13.4.8. CVE-2020-98717.8An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10CVE-2020-98727.8An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10CVE-2020-98737.8An out-of-bounds read was addressed with improved input validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6,CVE-2020-98747.8An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10CVE-2020-98757.8An integer overflow was addressed through improved input validation. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6CVE-2020-98767.8An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10CVE-2020-98777.8An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6, CVE-2020-98787.8A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10.15.6CVE-2020-98797.8An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.6 and iPadOS 13.6, macOS Catalina 10
CVE-2020-9866: Critical severity, CVSS 9.8 | Vulnix