CVE-2021-30807highunder attackCWE-787

CVE-2021-30807: high-severity vulnerability in Apple macOS

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81Vexday Risk Score

Prioritize patching. It under exploitation confirmed by CISA and has a public proof of concept.

ssvc Actcvss 7.8epss 29%
from disclosure to weaponsame day
Published on NVDOct 19
1st PoCJul 26
CISA KEV+15d
Action required by CISAfederal deadline: 2021-11-17

Apply updates per vendor instructions.

In short

A memory corruption flaw in Apple devices allows malicious apps to run code with kernel-level privileges, the highest access level on a system. This is especially serious because Apple confirmed it was already being exploited in the wild.

Technical detail

Out-of-bounds write vulnerability (CWE-787) affecting macOS Big Sur, iOS 14.7, and iPadOS 14.7 prior to specified patch versions. Local application execution is the attack vector; exploitation requires app installation but grants arbitrary code execution at kernel privilege level. Active exploitation in the wild reported.

Summary generated and translated by AI from the official description.

The full analysis of this CVE is available in Portuguese →

A memory corruption issue was addressed with improved memory handling. This issue is fixed in macOS Big Sur 11.5.1, iOS 14.7.1 and iPadOS 14.7.1, watchOS 7.6.1. An application may be able to execute arbitrary code with kernel privileges. Apple is aware of a report that this issue may have been actively exploited.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
Apple · macOS
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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