Linux Heap TCache Poisoning

Linux Heap TCache Poisoning

In this paper, I introduce the reader to a heap metadata corruption against the current Linux Heap Allocator, ptmalloc. The attack is performed via corrupting, or poisoning the tcache such that malloc returns an arbitrary pointer. This may allow for control flow hijacking if malloc returns a pointer to a function pointer and an attacker is able to write to that malloc returned buffer. TCache poisoning is possible from heap corruption including buffer overflows and Use-After-Frees.

Linux Heap TCache Poisoning.PDF

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