A use after free issue was addressed with improved memory management. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, watchOS 7.3, tvOS 14.4, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause a denial of service.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
| Link | Tags |
|---|---|
| https://support.apple.com/en-us/HT212147 | release notes vendor advisory |
| https://support.apple.com/en-us/HT212146 | release notes vendor advisory |
| https://support.apple.com/en-us/HT212148 | release notes vendor advisory |
| https://support.apple.com/en-us/HT212149 | release notes vendor advisory |