About the security content of macOS Big Sur 11.3.1

This document describes the security content of macOS Big Sur 11.3.1.

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macOS Big Sur 11.3.1

Released May 3, 2021

WebKit

Available for: macOS Big Sur

Impact: Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.

Description: A memory corruption issue was addressed with improved state management.

CVE-2021-30665: yangkang (@dnpushme)&zerokeeper&bianliang of 360 ATA

WebKit

Available for: macOS Big Sur

Impact: Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.

Description: An integer overflow was addressed with improved input validation.

CVE-2021-30663: an anonymous researcher

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