Skip to content

YARA · Google Cloud Threat Intelligence (GCTI)

GCTI_Cobaltstrike_Resources_Artifact64_V3_1_V3_2_V3_14_And_V4_0

Cobalt Strike's resources/artifact64{svcbig.exe,.dll,big.dll,svc.exe} and resources/artifactuac(big)64.dll signature for versions 3.14 to 4.x and resources/artifact32svc.exe for 3.14 to 4.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/artifact64{svcbig.exe,.dll,big.dll,svc.exe} and resources/artifactuac(big)64.dll signature for versions 3.14 to 4.x and resources/artifact32svc.exe for 3.14 to 4.x

Associated malware family: Cobalt Strike.

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

Summary generated from the rule's metadata and condition.

Rule source

cobaltstrike-resources-artifact64-v3-1-v3-2-v3-14-and-v4-0.yarApache License 2.0
rule GCTI_Cobaltstrike_Resources_Artifact64_V3_1_V3_2_V3_14_And_V4_0
{
	meta:
		description = "Cobalt Strike's resources/artifact64{svcbig.exe,.dll,big.dll,svc.exe} and resources/artifactuac(big)64.dll signature for versions 3.14 to 4.x and resources/artifact32svc.exe for 3.14 to 4.x"
		author = "gssincla@google.com"
		id = "c9e9b8e0-16fe-5abc-b1fe-0e3e586f6db6"
		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_Artifact64_v1_49_to_v4_x.yara#L56-L84"
		license_url = "https://github.com/chronicle/GCTI/blob/1c5fd42b1895098527fde00c2d9757edf6b303bb/LICENSE"
		hash = "2e7a39bd6ac270f8f548855b97c4cef2c2ce7f54c54dd4d1aa0efabeecf3ba90"
		logic_hash = "e5af04baa1d18d5a2a2c005b40bf93fe6a7b2d7116dfcf3c5b3fa36657448eb9"
		score = 75
		quality = 85
		tags = ""

	strings:
		$decoderFunction = { 31 ?? EB 0F 41 [2] 03 47 [3] 44 [3] 48 [2] 39 ?? 41 [2] 7C EA 4C [6] E9 }

	condition:
		$decoderFunction
}

Strings (1 patterns)

IdentifierTypeValueModifiers
$decoderFunctionhex{ 31 ?? EB 0F 41 [2] 03 47 [3] 44 [3] 48 [2] 39 ?? 41 [2] 7C EA 4C [6] E9 }

Condition

$decoderFunction

In plain words (Heuristic)

  • Pattern $decoderFunction must be present.

Test this rule in your browser

Drop a file to scan it with this rule using YARA-X compiled to WebAssembly. Nothing is uploaded.

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).

  • 2e7a39bd6ac270f8f548855b97c4cef2c2ce7f54c54dd4d1aa0efabeecf3ba90

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: c9e9b8e0-16fe-5abc-b1fe-0e3e586f6db6

More Cobalt Strike rules