CVE-2021-1820

A memory initialization issue was addressed with improved memory handling. This issue is fixed in macOS Big Sur 11.3, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5. Processing maliciously crafted web content may result in the disclosure of process memory.

• CWE-665

• https://support.apple.com/en-us/HT212317Vendor Advisory
• https://support.apple.com/en-us/HT212323Vendor Advisory
• https://support.apple.com/en-us/HT212324Vendor Advisory
• https://support.apple.com/en-us/HT212325Vendor Advisory
• https://support.apple.com/en-us/HT212317Vendor Advisory
• https://support.apple.com/en-us/HT212323Vendor Advisory
• https://support.apple.com/en-us/HT212324Vendor Advisory
• https://support.apple.com/en-us/HT212325Vendor Advisory

Published

Sep 8, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

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