CVE-2021-21941

A product performs a series of non-atomic actions to switch between contexts that cross privilege or other security boundaries, but a race condition allows an attacker to modify or misrepresent the product's behavior during the switch.

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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.