Diet LIBC House of Spirit

In this paper, I introduce the reader to a heap metadata corruption against the latest version of diet libc. This allocator is used in embedded systems. In the House of Spirit, an attacker passes a pointer to a fake chunk header to the free API. This chunk can be of almost arbitrary size. The allocator will subsequently insert this fake chunk into the global freelist. The next malloc of the appropriate size will return the fake chunk which may overlap data that may be of benefit to the attacker.

Diet LIBC House of Spirit.PDF

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Heap Exploitation in Chrome's PartitionAlloc - part 1

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Dr Silvio Cesare
@silviocesare
Summary PartitionAlloc is the hardened heap allocator used in Google's Chrome web browser. It is susceptible to a number of attacks. This blog post describes the first attack in a series of posts. I will talk about freelist poisoning and how to make an allocation request return an arbitrary pointer. This can be used with application-logic to develop an arbitrary write primitive.
Introduction In heap allocators, freelists maintain a group of free memory chunks that are available to be recycled by an allocation request. Freelist poisoning corrupts this list and injects a "fake chunk" pointer. A later allocation will return this fake chunk pointer. So it is possible to make an allocation request return an arbitrary pointer.

I have blogged about freelist poisoning extensively. It is a common attack that many allocators are vulnerable to.

https://blog.infosectcbr.com.au/2020/03/weaknesses-in-linux-kernel-heap.html
https://blog.infosectcbr.com.au/2…
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