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YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_Cobaltstrike_Sleep_Decoder_Indicator

Detects CobaltStrike sleep_mask decoder

Hack toolCobalt StrikeSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
yara@s3c.za.net
Date
2021-07-19
Modified
2023-12-05
Score / Quality
75 / 85

What this rule detects

Detects CobaltStrike sleep_mask decoder

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-sleep-decoder-indicator.yarDetection Rule License 1.1
rule SIGNATURE_BASE_Cobaltstrike_Sleep_Decoder_Indicator
{
	meta:
		description = "Detects CobaltStrike sleep_mask decoder"
		author = "yara@s3c.za.net"
		id = "d5b53d68-55f9-5837-9b0c-e7be2f3bd072"
		date = "2021-07-19"
		modified = "2023-12-05"
		reference = "https://github.com/Neo23x0/signature-base"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/apt_cobaltstrike_evasive.yar#L16-L26"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		logic_hash = "f3243c326df18edbd15c2d9120379588e61709efb9295b9584c0565c04ee38a5"
		score = 75
		quality = 85
		tags = ""

	strings:
		$sleep_decoder = { 48 89 5C 24 08 48 89 6C 24 10 48 89 74 24 18 57 48 83 EC 20 4C 8B 51 08 41 8B F0 48 8B EA 48 8B D9 45 8B 0A 45 8B 5A 04 4D 8D 52 08 45 85 C9 }

	condition:
		$sleep_decoder
}

Strings (1 patterns)

IdentifierTypeValueModifiers
$sleep_decoderhex{ 48 89 5C 24 08 48 89 6C 24 10 48 89 74 24 18 57 48 83 EC 20 4C 8B 51 08 41 8B F0 48 8B EA 48 8B D9 45 8B 0A 45 8B 5A 04 4D 8D 52 08 45 85 C9 }

Condition

$sleep_decoder

In plain words (Heuristic)

  • Pattern $sleep_decoder must be present.

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References

Licence & attribution

Author: yara@s3c.za.net

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: d5b53d68-55f9-5837-9b0c-e7be2f3bd072

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