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YARA · Signature Base (Florian Roth / Nextron)

SIGNATURE_BASE_HKTL_Redmimicry_Winntiloader

matches the Winnti 'Cooper' loader version used for the RedMimicry breach emulation

Hack toolWinntiSignature Base (Florian Roth / Nextron)Detection Rule License 1.1Compiles with YARA-X
Author
mirar@chaosmail.org
Date
2020-06-22
Modified
2023-01-10
Score / Quality
75 / 85

What this rule detects

matches the Winnti 'Cooper' loader version used for the RedMimicry breach emulation

Associated malware family: Winnti.

It defines 3 patterns (2 text, 1 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

hktl-redmimicry-winntiloader.yarDetection Rule License 1.1
rule SIGNATURE_BASE_HKTL_Redmimicry_Winntiloader
{
	meta:
		description = "matches the Winnti 'Cooper' loader version used for the RedMimicry breach emulation"
		author = "mirar@chaosmail.org"
		id = "a8be1377-faa0-560d-a12c-0369b1f91180"
		date = "2020-06-22"
		modified = "2023-01-10"
		reference = "https://redmimicry.com"
		source_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/yara/gen_redmimicry.yar#L28-L59"
		license_url = "https://github.com/Neo23x0/signature-base/blob/94a1c48d7ab499879287ff611dfe7f9c56376030/LICENSE"
		logic_hash = "d8ef457ac41a7c45cc7e97330bdd3de12eb3391c03d0a6a87ddc669c841c325d"
		score = 75
		quality = 85
		tags = ""
		sharing = "tlp:white"

	strings:
		$s0 = "Cooper" ascii fullword
		$s1 = "stone64.dll" ascii fullword
		$decoding_loop = { 49 63 D0 43 8D 0C 01 41 FF C0 42 32 0C 1A 0F B6 C1 C0 E9 04 C0 E0 04 02 C1 42 88 04 1A 44 3B 03 72 DE }

	condition:
		all of them
}

Strings (3 patterns)

IdentifierTypeValueModifiers
$s0text"Cooper"ascii fullword
$s1text"stone64.dll"ascii fullword
$decoding_loophex{ 49 63 D0 43 8D 0C 01 41 FF C0 42 32 0C 1A 0F B6 C1 C0 E9 04 C0 E0 04 02 C1 42 88 04 1A 44 3B 03 72 DE }

Condition

all of them

In plain words (Heuristic)

  • All patterns in the rule must match.

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References

Licence & attribution

Author: mirar@chaosmail.org

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: a8be1377-faa0-560d-a12c-0369b1f91180

Metadata

sharingtlp:white

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