SUSP_NET_Large_Static_Array_In_Small_File_Jan24

YARA detection rule by Jonathan Peters · NOASSERTION

Detects large static arrays in small .NET files

import "pe"
rule SUSP_NET_Large_Static_Array_In_Small_File_Jan24 {
   meta:
      description = "Detects large static arrays in small .NET files "
      author = "Jonathan Peters"
      date = "2024-01-11"
      reference = "https://github.com/Workingdaturah/Payload-Generator/tree/main"
      hash = "7d68bfaed20d4d7cf2516c2b110f460cf113f81872cd0cc531cbfa63a91caa36"
      score = 60
   strings:
      $op = { 5F 5F 53 74 61 74 69 63 41 72 72 61 79 49 6E 69 74 54 79 70 65 53 69 7A 65 3D [6-] 00 }
   condition:
      uint16(0) == 0x5a4d and
	  pe.data_directories[pe.IMAGE_DIRECTORY_ENTRY_COM_DESCRIPTOR].virtual_address != 0 and
	  filesize < 300KB and
	  #op == 1
}

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

6c1855b5-1482-4af3-ae9c-3b571e449015

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

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Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

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[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

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