45 lines
1.5 KiB
Markdown
45 lines
1.5 KiB
Markdown
# What day-zero dug up in tcpip.sys
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Windows TCP/IP driver, 8,421 functions, no symbols. These are leads, not
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confirmed bugs — spots worth opening in Ghidra, not proof of anything.
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A length going into `NdisGetDataBuffer`:
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```
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len = ((arg2 & 0xf) << 2) - 20
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```
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Low nibble times 4, minus 20 — a header-length field in 4-byte words with a
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20-byte header subtracted off. Nibble under 5 and it underflows to ~4GB.
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A length walked through four functions, none of them bounding it, from a network
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entry point down into a packet parser:
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```
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0x1400557d0 -> 0x140053d04 -> 0x14006323c -> 0x140061850 -> NdisGetDataBuffer
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```
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Every hop assumes someone else checked it.
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A handful of WFP functions (`WfpBufferCopy`,
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`WfpHandOffTupleStateToTemporaryAleEntry`) hand an unchecked value straight to
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`ExAllocatePool2` as the allocation size. One computes it as `(input << 4) + 0x2e`
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— multiply attacker input by 16, allocate that.
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And the spots that *do* bound the same `(nibble << 2)` length with a proper
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`<= 0x14` check — flagged as fine, not as findings.
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# Usage
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Easy start:
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```py binspect.py tcpip.sys --trace```
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### How I made it
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Been working on it since a few months. Hope it's useful for your research!
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### Contributions
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Contributions are welcome, just fork it, edit it and do a Pull Request!
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# Disclaimer & License
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Friendly Reminder: reuploads, translations, and edits without permission will get you striked. You know who you are. I know who you are. So don't do it please
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