CVE-2021-30661

A use after free issue was addressed with improved memory management. This issue is fixed in Safari 14.1, iOS 12.5.3, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3. 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..

• CWE-416
• CWE-416

• https://support.apple.com/en-us/HT212317Vendor Advisory
• https://support.apple.com/en-us/HT212318Vendor 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/HT212341Vendor Advisory
• https://support.apple.com/en-us/HT212317Vendor Advisory
• https://support.apple.com/en-us/HT212318Vendor 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/HT212341Vendor Advisory
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30661Third Party Advisory, US Government Resource

Published

Sep 8, 2021

Last Modified

Jun 17, 2026

Status

Analyzed

• 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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