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MALPEDIA_Win_Kutaki_Auto

autogenerated rule brought to you by yara-signator

MalwareKutakiMalpedia signator rulesCreative Commons Attribution-ShareAlike 4.0Compiles with YARA-X
Author
Felix Bilstein - yara-signator at cocacoding dot com
Date
2026-05-04
Modified
2026-05-18
Score / Quality
75 / 75

What this rule detects

autogenerated rule brought to you by yara-signator

Associated malware family: Kutaki.

It defines 10 patterns (0 text, 10 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

win-kutaki-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Kutaki_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "48e743da-b335-5755-b568-4eed1a0848ba"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.kutaki"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.kutaki_auto.yar#L1-L131"
		license_url = "N/A"
		logic_hash = "f1fa7380a50e2743cedeaaa0693c41429b0def91858704e16479700f8e6c6e01"
		score = 75
		quality = 75
		tags = "FILE"
		version = "1"
		tool = "yara-signator v0.6.0"
		signator_config = "callsandjumps;datarefs;binvalue"
		malpedia_rule_date = "20260422"
		malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
		malpedia_version = "20260504"
		malpedia_license = "CC BY-SA 4.0"
		malpedia_sharing = "TLP:WHITE"

	strings:
		$sequence_0 = { e9???????? c745fc0a000000 c745fc0b000000 8b450c 6bc004 0f8037080000 83c002 }
		$sequence_1 = { 83bd80feffff00 7d26 68a0000000 68???????? 8b9584feffff 52 8b8580feffff }
		$sequence_2 = { 8d4de0 ff15???????? 8b4d08 6a00 8b11 8955c4 ffd3 }
		$sequence_3 = { c7458c00000000 8b4d8c f7d9 66894db4 8d4ddc ff15???????? 8d4dd4 }
		$sequence_4 = { ff15???????? 898584fcffff eb0a c78584fcffff00000000 8b9574ffffff 899564fdffff c78574ffffff00000000 }
		$sequence_5 = { 66833801 7543 8b4dac 8b55d8 2b5114 899554ffffff }
		$sequence_6 = { 8d9574ffffff 8d4da4 ff15???????? 8b4dc8 898d20ffffff c745c800000000 }
		$sequence_7 = { 8d4598 52 50 6a03 ff15???????? 83c41c 68???????? }
		$sequence_8 = { 51 ff15???????? 8d8d3cffffff ff15???????? c745fc0a000000 83bd68ffffff00 }
		$sequence_9 = { e9???????? c745fc34000000 8d45ac 50 e8???????? 8bd0 8d4da8 }

	condition:
		7 of them and filesize < 1335296
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ e9???????? c745fc0a000000 c745fc0b000000 8b450c 6bc004 0f8037080000 83c002 }
$sequence_1hex{ 83bd80feffff00 7d26 68a0000000 68???????? 8b9584feffff 52 8b8580feffff }
$sequence_2hex{ 8d4de0 ff15???????? 8b4d08 6a00 8b11 8955c4 ffd3 }
$sequence_3hex{ c7458c00000000 8b4d8c f7d9 66894db4 8d4ddc ff15???????? 8d4dd4 }
$sequence_4hex{ ff15???????? 898584fcffff eb0a c78584fcffff00000000 8b9574ffffff 899564fdffff c78574ffffff00000000 }
$sequence_5hex{ 66833801 7543 8b4dac 8b55d8 2b5114 899554ffffff }
$sequence_6hex{ 8d9574ffffff 8d4da4 ff15???????? 8b4dc8 898d20ffffff c745c800000000 }
$sequence_7hex{ 8d4598 52 50 6a03 ff15???????? 83c41c 68???????? }
$sequence_8hex{ 51 ff15???????? 8d8d3cffffff ff15???????? c745fc0a000000 83bd68ffffff00 }
$sequence_9hex{ e9???????? c745fc34000000 8d45ac 50 e8???????? 8bd0 8d4da8 }

Condition

7 of them and filesize < 1335296

In plain words (Heuristic)

  • The file must be smaller than 1335296 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

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References

Licence & attribution

Author: Felix Bilstein - yara-signator at cocacoding dot com

Source repository: Malpedia signator rules @ c901f97b7d

Licence: Creative Commons Attribution-ShareAlike 4.0 (repository licence)

Original rule

Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.

Rule id: 48e743da-b335-5755-b568-4eed1a0848ba

Metadata

version1
toolyara-signator v0.6.0
signator_configcallsandjumps;datarefs;binvalue
malpedia_rule_date20260422
malpedia_hasha182e35da64e6d71cb55f125c4d4225196523f14
malpedia_version20260504
malpedia_licenseCC BY-SA 4.0
malpedia_sharingTLP:WHITE

Tags:FILE