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YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_SUSP_Doc_Windowsinstaller_Call_Feb22_1

Triggers on docfiles executing windows installer. Used for deploying ThinBasic scripts.

Suspicious / huntingSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
Nils Kuhnert
Date
2022-02-26
Modified
2023-12-05
Score / Quality
65 / 85

What this rule detects

Triggers on docfiles executing windows installer. Used for deploying ThinBasic scripts.

Targets: OLE / legacy Office.

It defines 3 patterns (3 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

susp-doc-windowsinstaller-call-feb22-1.yarDetection Rule License 1.1
rule SIGNATURE_BASE_SUSP_Doc_Windowsinstaller_Call_Feb22_1 : FILE
{
	meta:
		description = "Triggers on docfiles executing windows installer. Used for deploying ThinBasic scripts."
		author = "Nils Kuhnert"
		id = "8f2e8f91-74e0-5574-9c0a-1479d6114212"
		date = "2022-02-26"
		modified = "2023-12-05"
		reference = "https://twitter.com/threatinsight/status/1497355737844133895"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/gen_maldoc.yar#L1-L16"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		logic_hash = "279182487ab7d35264adfbd0d122ee7634cd92ae1711de78ec7f20928df34f49"
		score = 65
		quality = 85
		tags = "FILE"
		tlp = "white"

	strings:
		$ = "WindowsInstaller.Installer$"
		$ = "CreateObject"
		$ = "InstallProduct"

	condition:
		uint32be( 0 ) == 0xd0cf11e0 and all of them
}

Strings (3 patterns)

IdentifierTypeValueModifiers
$text"WindowsInstaller.Installer$"
$text"CreateObject"
$text"InstallProduct"

Condition

uint32be( 0 ) == 0xd0cf11e0 and all of them

In plain words (Heuristic)

  • The file must start with the OLE header — legacy Office documents, MSI.
  • All patterns in the rule must match.

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References

Licence & attribution

Author: Nils Kuhnert

Source repository: Signature Base (Florian Roth / Nextron) @ 94a1c48d7a

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: 8f2e8f91-74e0-5574-9c0a-1479d6114212

Metadata

tlpwhite

Tags:FILE