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Add rule unhook-a-dll.yml #921

Merged
merged 2 commits into from
Aug 15, 2024
Merged

Add rule unhook-a-dll.yml #921

merged 2 commits into from
Aug 15, 2024

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jtothej
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@jtothej jtothej commented Aug 11, 2024

Add rule unhook-a-dll.yml

@@ -0,0 +1,26 @@
rule:
meta:
name: unhook a DLL
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the reference talks about overwriting ntdll's .text section to remove hooks, should we adjust the rule name and logic to that specific usage?

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I initially created the rule specifically for NTDLL but then decided to make it more generic. Most likely NTDLL will be the unhooking target in most samples anyway but I wanted to match also on less common DLLs. If you think the rule is too broad I'll change it to its initial form.

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hm, I think it shouldn't result in many FPs and if so, we can fine tune it
for when we do come back to it later, can you please add this comment to the rule?

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and how about renaming to better reflect what's captured here, e.g. overwrite DLL .text section to remove hooks or similar?

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Thanks for suggestions! Updated the rule in 3a03215

- 282c32269a9893c5741ca682268369421c43ac21d73b1f6c23386d61c93bf3e9:0x1400014A4
features:
- and:
- api: GetModuleHandle
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add GetModuleHandleEx?

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Added in 3a03215

@@ -0,0 +1,26 @@
rule:
meta:
name: unhook a DLL
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hm, I think it shouldn't result in many FPs and if so, we can fine tune it
for when we do come back to it later, can you please add this comment to the rule?

@@ -0,0 +1,26 @@
rule:
meta:
name: unhook a DLL
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and how about renaming to better reflect what's captured here, e.g. overwrite DLL .text section to remove hooks or similar?

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great, thank you very much!

@mr-tz mr-tz merged commit 1d4b140 into mandiant:master Aug 15, 2024
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2 participants