Windows Heap Exploitation (Win2KSP0 through WinXPS…….pptVIP

下载本文档

37
0
约1.65万字
约 59页
2017-03-31 发布于广东
举报
版权申诉

Windows Heap Exploitation (Win2KSP0 through WinXPS…….ppt

1、本文档共59页，可阅读全部内容。
2、有哪些信誉好的足球投注网站（book118）网站文档一经付费（服务费），不意味着购买了该文档的版权，仅供个人/单位学习、研究之用，不得用于商业用途，未经授权，严禁复制、发行、汇编、翻译或者网络传播等，侵权必究。
3、本站所有内容均由合作方或网友上传，本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺！文档内容仅供研究参考，付费前请自行鉴别。如您付费，意味着您自己接受本站规则且自行承担风险，本站不退款、不进行额外附加服务；查看《如何避免下载的几个坑》。如果您已付费下载过本站文档，您可以点击这里二次下载。
4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等，请点击“版权申诉”（推荐），也可以打举报电话：400-050-0827(电话支持时间：9:00-18:30)。
5、该文档为VIP文档，如果想要下载，成为VIP会员后，下载免费。
6、成为VIP后，下载本文档将扣除1次下载权益。下载后，不支持退款、换文档。如有疑问请联系我们。
7、成为VIP后，您将拥有八大权益，权益包括：VIP文档下载权益、阅读免打扰、文档格式转换、高级专利检索、专属身份标志、高级客服、多端互通、版权登记。
8、VIP文档为合作方或网友上传，每下载1次，网站将根据用户上传文档的质量评分、类型等，对文档贡献者给予高额补贴、流量扶持。如果你也想贡献VIP文档。上传文档

Windows Heap Exploitation (Win2KSP0 through WinXPS…….ppt

Windows Heap Exploitation(Win2KSP0 through WinXPSP2) Agenda “Practical” Windows heap internals How to exploit Win2K – WinXP SP1 heap overflows 3rd party (me ?) assessment of WinXP SP2 improvements How to exploit WinXP SP2 heap overflows Summary Windows Heap Internals Many heaps can coexist in one process (normally 2-3) Windows Heap Internals Important heap structures Windows Heap Internals Introduction to Free Lists 128 doubly-linked list of free chunks (from 8 bytes to 1024 bytes) Chunk size is table row index * 8 bytes Entry [0] is a variable sized free lists contains buffers of 1KB = size 512KB, sorted in ascending order Windows Heap Internals Lookaside Table Used for “fast” allocates and deallocates when available Starts empty 128 singly-linked lists of busy chunks (free but left marked as busy) Windows Heap Internals Why have lookasides at all? Speed! Singly-linked Used to quickly allocate or deallocate No coalescing (leads to fragmentation) So the lookaside lists “fill up” quickly (4 entries) Windows Heap Internals Basic chunk structure – 8 Bytes Windows Heap Internals Free chunk structure – 16 Bytes Windows Heap Internals Allocation algorithm (high level) If size = 512K, virtual memory is used (not on heap) If 1K, first check the Lookaside lists. If there is no free entries on the Lookaside, check the matching free list If = 1K or no matching entry was found, use the heap cache (not discussed in this presentation). If = 1K and no free entry in the heap cache, use FreeLists[0] (the variable sized free list) If still can’t find any free entry, extend heap as needed Windows Heap Internals Allocate algorithm – FreeLists[0] This is usually what happens for chunk sizes 1K FreeLists[0] is sorted from smallest to biggest Check if FreeLists[0]-Blink to see if it is big enough (the biggest block) Then return the smallest free entry from free list[0] to fulfill the request, like this: While (Entry-Size NeededSize) Entry = Entry-Flink Windows Heap Internals Allo