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YARA · Avast / Gen Digital IOC

AVASTTI_Cobaltstrike_Strike_Payload_Xored

No description has been set in the source file - AvastTI

Hack toolCobalt StrikeAvast / Gen Digital IOCDetection Rule License 1.1Compiles with YARA-X
Author
Gen Threat Labs
Date
2021-07-08
Modified
2026-03-11
Score / Quality
75 / 90

What this rule detects

No description has been set in the source file - AvastTI

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

Download .yar
cobaltstrike-strike-payload-xored.yarDetection Rule License 1.1
rule AVASTTI_Cobaltstrike_Strike_Payload_Xored
{
	meta:
		description = "No description has been set in the source file - AvastTI"
		author = "Gen Threat Labs"
		id = "0e075644-e278-5c5b-bdcc-dc2d6a32ce73"
		date = "2021-07-08"
		modified = "2026-03-11"
		reference = "https://github.com/gendigitalinc/ioc"
		source_url = "https://github.com/avast/ioc/blob/a450ddabed95984422909c75ac52b6841f685983/CobaltStrike/yara_rules/cs_rules.yar#L595-L613"
		license_url = "N/A"
		logic_hash = "532cf38554ad7211fab74d050007f6fe8d63c20e05f21a6737fff12ac92a81d7"
		score = 75
		quality = 90
		tags = ""

	strings:
		$h01 = { 10 ?? 00 00 ?? ?? ?? 00 ?? ?? ?? ?? 61 61 61 61 }

	condition:
		uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0xFCE88900 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0xFC4883E4 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0x4D5AE800 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0x4D5A4152 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0x90909090
}

Strings (1 patterns)

IdentifierTypeValueModifiers
$h01hex{ 10 ?? 00 00 ?? ?? ?? 00 ?? ?? ?? ?? 61 61 61 61 }

Condition

uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0xFCE88900 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0xFC4883E4 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0x4D5AE800 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0x4D5A4152 or uint32be( @h01 + 8 ) ^ uint32be( @h01 + 16 ) == 0x90909090

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References

Licence & attribution

Author: Gen Threat Labs

Source repository: Avast / Gen Digital IOC @ a450ddabed

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: 0e075644-e278-5c5b-bdcc-dc2d6a32ce73

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