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SEKOIA_Installer_Win_Minibus

Detect MINIBUS installer

MalwareMinibusSEKOIA.IO CommunityDetection Rule License 1.1Compiles with YARA-X (with warnings)
Author
Sekoia.io
Date
2024-04-08
Modified
2024-12-19
Score / Quality
75 / 80

What this rule detects

Detect MINIBUS installer

Associated malware family: Minibus.

Targets: Windows PE.

It defines 2 patterns (2 text, 0 hex, 0 regex). YARA modules used: pe, hash.

YARA-X says: warning[deprecated_field]: field `number_of_resources` is deprecated

Summary generated from the rule's metadata and condition.

Rule source

Includes the imports needed to compile it on its own.

installer-win-minibus.yarDetection Rule License 1.1
import "pe"
import "hash"

rule SEKOIA_Installer_Win_Minibus : FILE
{
	meta:
		description = "Detect MINIBUS installer"
		author = "Sekoia.io"
		id = "0f7f600d-d93b-4b5a-aa0e-7d91038409e6"
		date = "2024-04-08"
		modified = "2024-12-19"
		reference = "https://github.com/SEKOIA-IO/Community"
		source_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/installer_win_minibus.yar#L4-L27"
		license_url = "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
		hash = "26ca51cb067e1fdf1b8ad54ba49883bc5d1945952239aec0c4840754bff76621"
		hash = "90fa29cc98be1d715df26d22079bdb8ce1d1fd3ce6a4efb39a4c192134e01020"
		logic_hash = "24326c9f5dcb7e66d47b65bf6bec6fe78be18c8d41a3039fbd09b453568a3f8f"
		score = 75
		quality = 80
		tags = "FILE"
		version = "1.0"
		classification = "TLP:CLEAR"

	strings:
		$ = "\\essential.dat"
		$ = "TorvaldInitial.dll"

	condition:
		uint16be( 0 ) == 0x4d5a and 1 of them or for any i in ( 0 .. pe.number_of_resources -1 ) : ( hash.sha256 ( pe.resources [ i ] . offset , pe.resources [ i ] . length ) == "de3fb5d4419eb6b943872dd6e3dd93d19584ef2b158aa3158b3b09f0a9b628ef" )
}

Strings (2 patterns)

IdentifierTypeValueModifiers
$text"\\essential.dat"
$text"TorvaldInitial.dll"

Condition

uint16be( 0 ) == 0x4d5a and 1 of them or for any i in ( 0 .. pe.number_of_resources -1 ) : ( hash.sha256 ( pe.resources [ i ] . offset , pe.resources [ i ] . length ) == "de3fb5d4419eb6b943872dd6e3dd93d19584ef2b158aa3158b3b09f0a9b628ef" )

In plain words (Heuristic)

  • The file must start with “MZ” — a Windows executable (PE).
  • At least 1 patterns in the rule must match.
  • A for-loop checks a property over several matches or items.
  • Uses the pe module.
  • Uses the hash module.
  • Compares a hash of the file or a part of it.

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Drop a file here or click to chooseScanned locally with YARA-X. Files up to 200 MB.

Open in editor

References

Sample hashes

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

  • 26ca51cb067e1fdf1b8ad54ba49883bc5d1945952239aec0c4840754bff76621
  • 90fa29cc98be1d715df26d22079bdb8ce1d1fd3ce6a4efb39a4c192134e01020

Licence & attribution

Author: Sekoia.io

Source repository: SEKOIA.IO Community @ a438a5901a

Licence: Detection Rule License 1.1 (repository licence)

Original rule

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

Rule id: 0f7f600d-d93b-4b5a-aa0e-7d91038409e6

Metadata

version1.0
classificationTLP:CLEAR

Tags:FILE

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