A use after free issue was addressed with improved memory management. This issue is fixed in iOS 13.6 and iPadOS 13.6, tvOS 13.4.8, watchOS 6.2.8, iCloud for Windows 7.20, macOS Catalina 10.15.6, Security Update 2020-004 Mojave, Security Update 2020-004 High Sierra. Processing maliciously crafted XML may lead to an unexpected application termination or arbitrary code execution.
Weakness
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 Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Icloud | Apple | * | 7.20 (excluding) |
| Ipados | Apple | * | 13.6 (excluding) |
| Iphone_os | Apple | * | 13.6 (excluding) |
| Mac_os_x | Apple | * | 10.13.6 (excluding) |
| Mac_os_x | Apple | 10.14 (including) | 10.14.6 (excluding) |
| Mac_os_x | Apple | 10.15 (including) | 10.15.6 (excluding) |
| Mac_os_x | Apple | 10.13.6 (including) | 10.13.6 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2018-002 (including) | 10.13.6-security_update_2018-002 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2018-003 (including) | 10.13.6-security_update_2018-003 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-001 (including) | 10.13.6-security_update_2019-001 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-002 (including) | 10.13.6-security_update_2019-002 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-003 (including) | 10.13.6-security_update_2019-003 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-004 (including) | 10.13.6-security_update_2019-004 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-005 (including) | 10.13.6-security_update_2019-005 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-006 (including) | 10.13.6-security_update_2019-006 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2019-007 (including) | 10.13.6-security_update_2019-007 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2020-001 (including) | 10.13.6-security_update_2020-001 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2020-002 (including) | 10.13.6-security_update_2020-002 (including) |
| Mac_os_x | Apple | 10.13.6-security_update_2020-003 (including) | 10.13.6-security_update_2020-003 (including) |
| Mac_os_x | Apple | 10.13.6-supplemental_update (including) | 10.13.6-supplemental_update (including) |
| Mac_os_x | Apple | 10.14.6 (including) | 10.14.6 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2019-001 (including) | 10.14.6-security_update_2019-001 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2019-002 (including) | 10.14.6-security_update_2019-002 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2020-001 (including) | 10.14.6-security_update_2020-001 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2020-002 (including) | 10.14.6-security_update_2020-002 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2020-003 (including) | 10.14.6-security_update_2020-003 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2020-004 (including) | 10.14.6-security_update_2020-004 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2020-005 (including) | 10.14.6-security_update_2020-005 (including) |
| Mac_os_x | Apple | 10.14.6-security_update_2020-006 (including) | 10.14.6-security_update_2020-006 (including) |
| Mac_os_x | Apple | 10.14.6-supplemental_update (including) | 10.14.6-supplemental_update (including) |
| Mac_os_x | Apple | 10.14.6-supplemental_update_2 (including) | 10.14.6-supplemental_update_2 (including) |
| Tvos | Apple | * | 13.4.8 (excluding) |
| Watchos | Apple | * | 6.2.8 (excluding) |
| Libxml2 | Ubuntu | trusty | * |
| Libxml2 | Ubuntu | xenial | * |
Potential Mitigations
References
- https://support.apple.com/en-us/HT211288
- https://support.apple.com/en-us/HT211289
- https://support.apple.com/en-us/HT211290
- https://support.apple.com/en-us/HT211291
- https://support.apple.com/en-us/HT211295
- https://support.apple.com/en-us/HT211288
- https://support.apple.com/en-us/HT211289
- https://support.apple.com/en-us/HT211290
- https://support.apple.com/en-us/HT211291
- https://support.apple.com/en-us/HT211295