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YARA · Mandiant red team tool countermeasures

FIREEYE_RT_Loader_MSIL_Wildchild_1

The TypeLibGUID present in a .NET binary maps directly to the ProjectGuid found in the '.csproj' file of a .NET project. This rule looks for .NET PE files that contain the ProjectGuid found in the WildChild project.

MalwareMandiant red team tool countermeasuresBSD 2-Clause LicenseCompiles with YARA-X
Author
FireEye
Date
2020-12-08
Modified
2020-12-09
Score / Quality
75 / 73

What this rule detects

The TypeLibGUID present in a .NET binary maps directly to the ProjectGuid found in the '.csproj' file of a .NET project. This rule looks for .NET PE files that contain the ProjectGuid found in the WildChild project.

Targets: Windows PE.

It defines 1 patterns (1 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

loader-msil-wildchild-1.yarBSD 2-Clause License
rule FIREEYE_RT_Loader_MSIL_Wildchild_1 : FILE
{
	meta:
		description = "The TypeLibGUID present in a .NET binary maps directly to the ProjectGuid found in the '.csproj' file of a .NET project. This rule looks for .NET PE files that contain the ProjectGuid found in the WildChild project."
		author = "FireEye"
		id = "350dd658-46c9-573b-b532-07e4b437ba8d"
		date = "2020-12-08"
		modified = "2020-12-09"
		reference = "https://github.com/mandiant/red_team_tool_countermeasures/"
		source_url = "https://github.com/mandiant/red_team_tool_countermeasures//blob/3561b71724dbfa3e2bb78106aaa2d7f8b892c43b/rules/WILDCHILD/production/yara/Loader_MSIL_WildChild_1.yar#L4-L15"
		license_url = "https://github.com/mandiant/red_team_tool_countermeasures//blob/3561b71724dbfa3e2bb78106aaa2d7f8b892c43b/LICENSE.txt"
		hash = "7e6bc0ed11c2532b2ae7060327457812"
		logic_hash = "e4320e33770613542182518ec787e4ccbb32f83c8afca5ec957d4846e6f4eb04"
		score = 75
		quality = 73
		tags = "FILE"
		rev = 4

	strings:
		$typelibguid1 = "2e71d5ff-ece4-4006-9e98-37bb724a7780" ascii nocase wide

	condition:
		( uint16( 0 ) == 0x5A4D and uint32( uint32( 0x3C ) ) == 0x00004550 ) and $typelibguid1
}

Strings (1 patterns)

IdentifierTypeValueModifiers
$typelibguid1text"2e71d5ff-ece4-4006-9e98-37bb724a7780"ascii nocase wide

Condition

( uint16( 0 ) == 0x5A4D and uint32( uint32( 0x3C ) ) == 0x00004550 ) and $typelibguid1

In plain words (Heuristic)

  • The file must start with “MZ” — a Windows executable (PE).
  • Pattern $typelibguid1 must be present.

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References

Sample hashes

Hashes of samples the author lists in the rule's meta (look them up in your threat-intelligence platform).

  • 7e6bc0ed11c2532b2ae7060327457812

Licence & attribution

Author: FireEye

Source repository: Mandiant red team tool countermeasures @ 3561b71724

Licence: BSD 2-Clause License (repository licence)

Copyright notice: Copyright (c) 2023, MANDIANT

Original rule

Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.

Rule id: 350dd658-46c9-573b-b532-07e4b437ba8d

Metadata

rev4

Tags:FILE