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GCTI_Cobaltstrike_Resources_Template_Sct_V3_3_To_V4_X

Cobalt Strike's resources/template.sct signature for versions v3.3 to v4.x

Hack toolCobalt StrikeGoogle Cloud Threat Intelligence (GCTI)Apache License 2.0Compiles with YARA-X
Author
gssincla@google.com
Date
2022-11-18
Modified
2022-11-19
Score / Quality
75 / 85

What this rule detects

Cobalt Strike's resources/template.sct signature for versions v3.3 to v4.x

Associated malware family: Cobalt Strike.

It defines 8 patterns (8 text, 0 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

cobaltstrike-resources-template-sct-v3-3-to-v4-x.yarApache License 2.0
rule GCTI_Cobaltstrike_Resources_Template_Sct_V3_3_To_V4_X
{
	meta:
		description = "Cobalt Strike's resources/template.sct signature for versions v3.3 to v4.x"
		author = "gssincla@google.com"
		id = "9d2b1dfa-5f76-503f-9198-6ed0d039e0cb"
		date = "2022-11-18"
		modified = "2022-11-19"
		reference = "https://cloud.google.com/blog/products/identity-security/making-cobalt-strike-harder-for-threat-actors-to-abuse"
		source_url = "https://github.com/chronicle/GCTI/blob/1c5fd42b1895098527fde00c2d9757edf6b303bb/YARA/CobaltStrike/CobaltStrike__Resources_Template_Sct_v3_3_to_v4_x.yara#L17-L38"
		license_url = "https://github.com/chronicle/GCTI/blob/1c5fd42b1895098527fde00c2d9757edf6b303bb/LICENSE"
		hash = "fc66cb120e7bc9209882620f5df7fdf45394c44ca71701a8662210cf3a40e142"
		logic_hash = "8868445ced4945c469764b7f311d6cb11c99cf0f2d770113e5e617e0187a962c"
		score = 75
		quality = 85
		tags = ""

	strings:
		$scriptletstart = "<scriptlet>" nocase
		$registration = "<registration progid=" nocase
		$classid = "classid=" nocase
		$scriptlang = "<script language=\"vbscript\">" nocase
		$cdata = "<![CDATA["
		$scriptend = "</script>" nocase
		$antiregistration = "</registration>" nocase
		$scriptletend = "</scriptlet>"

	condition:
		all of them and @scriptletstart [ 1 ] < @registration [ 1 ] and @registration [ 1 ] < @classid [ 1 ] and @classid [ 1 ] < @scriptlang [ 1 ] and @scriptlang [ 1 ] < @cdata [ 1 ]
}

Strings (8 patterns)

IdentifierTypeValueModifiers
$scriptletstarttext"<scriptlet>"nocase
$registrationtext"<registration progid="nocase
$classidtext"classid="nocase
$scriptlangtext"<script language=\"vbscript\">"nocase
$cdatatext"<![CDATA["
$scriptendtext"</script>"nocase
$antiregistrationtext"</registration>"nocase
$scriptletendtext"</scriptlet>"

Condition

all of them and @scriptletstart [ 1 ] < @registration [ 1 ] and @registration [ 1 ] < @classid [ 1 ] and @classid [ 1 ] < @scriptlang [ 1 ] and @scriptlang [ 1 ] < @cdata [ 1 ]

In plain words (Heuristic)

  • All patterns in the rule must match.

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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).

  • fc66cb120e7bc9209882620f5df7fdf45394c44ca71701a8662210cf3a40e142

Licence & attribution

Author: gssincla@google.com

Source repository: Google Cloud Threat Intelligence (GCTI) @ 1c5fd42b18

Licence: Apache License 2.0 (repository licence)

Original rule

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

Rule id: 9d2b1dfa-5f76-503f-9198-6ed0d039e0cb

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