win_cobalt_sleep_encrypt

YARA detection rule by Matthew @ Embee_Research

Detects Sleep Encryption Logic Found in Cobalt Strike Deployments

rule win_cobalt_sleep_encrypt
{
	meta:
		author = "Matthew @ Embee_Research"
		created = "2023/08/27"
		description = "Detects Sleep Encryption Logic Found in Cobalt Strike Deployments"
		sha_256 = "26b2f12906c3590c8272b80358867944fd86b9f2cc21ee6f76f023db812e5bb1"
		
	strings:
	
		
		
		
		$r1_nokey = {4E 8B 04 08 B8 ?? ?? ?? ?? 41 F7 E3 41 8B C3 C1 EA 02 41 FF C3 6B D2 0D 2B C2 8A 4C 18 18 41 30 0C 38 48 8B 43 10 41 8B FB 4A 3B 7C 08 08}

		$r2_nokey = {49 8B F9 4C 8B 03 B8 ?? ?? ?? ?? 41 F7 E1 41 8B C1 C1 EA 02 41 FF C1 6B D2 0D 2B C2 8A 4C 18 18 42 30 0C 07 48 FF C7 45 3B CB}
		
	condition:
						($r1_nokey or $r2_nokey)
		

}

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

3b1b3eda-0ba0-40ed-ae10-aa40cdbef68f

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

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Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

[[ reason ]]

What do these messages mean?

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

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