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MALPEDIA_Win_Kuaibu8_Auto

autogenerated rule brought to you by yara-signator

MalwareKuaibu8Malpedia 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: Kuaibu8.

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

Summary generated from the rule's metadata and condition.

Rule source

win-kuaibu8-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Kuaibu8_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "677a7b27-8dba-50f8-a903-d3ae3dd1454a"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.kuaibu8"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.kuaibu8_auto.yar#L1-L132"
		license_url = "N/A"
		logic_hash = "0baf0af63f21cd612a4fdefb8c0477dd54dc083c1e606251e564162b27012807"
		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 = { 7404 3c5c 7503 c60100 8d8c2410010000 51 e8???????? }
		$sequence_1 = { 8b9698160000 8b4c2414 42 899698160000 81e1ff000000 33d2 8a91e08b4300 }
		$sequence_2 = { 5b 81c440030000 c21000 3b7810 7d09 50 e8???????? }
		$sequence_3 = { 83c404 e9???????? 8965f0 ff75fc ff15???????? 90 90 }
		$sequence_4 = { 8945ec 6804000080 6a00 68???????? 6804000080 6a00 a1???????? }
		$sequence_5 = { 50 56 e8???????? 5e 81c40c010000 c3 b8fdffffff }
		$sequence_6 = { 51 c1e810 50 899524010000 e8???????? 83c408 }
		$sequence_7 = { 0f8406000000 8bca 33c0 f3ab ff75fc e8???????? 83c404 }
		$sequence_8 = { 8d942454020000 68???????? 52 e8???????? 8d44242c 50 6a00 }
		$sequence_9 = { 33d2 8a90e08a4300 8bc2 66ff848680090000 8b8694160000 8b8e98160000 }

	condition:
		7 of them and filesize < 737280
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 7404 3c5c 7503 c60100 8d8c2410010000 51 e8???????? }
$sequence_1hex{ 8b9698160000 8b4c2414 42 899698160000 81e1ff000000 33d2 8a91e08b4300 }
$sequence_2hex{ 5b 81c440030000 c21000 3b7810 7d09 50 e8???????? }
$sequence_3hex{ 83c404 e9???????? 8965f0 ff75fc ff15???????? 90 90 }
$sequence_4hex{ 8945ec 6804000080 6a00 68???????? 6804000080 6a00 a1???????? }
$sequence_5hex{ 50 56 e8???????? 5e 81c40c010000 c3 b8fdffffff }
$sequence_6hex{ 51 c1e810 50 899524010000 e8???????? 83c408 }
$sequence_7hex{ 0f8406000000 8bca 33c0 f3ab ff75fc e8???????? 83c404 }
$sequence_8hex{ 8d942454020000 68???????? 52 e8???????? 8d44242c 50 6a00 }
$sequence_9hex{ 33d2 8a90e08a4300 8bc2 66ff848680090000 8b8694160000 8b8e98160000 }

Condition

7 of them and filesize < 737280

In plain words (Heuristic)

  • The file must be smaller than 737280 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

Test this rule in your browser

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Drop a file here or click to chooseScanned locally with YARA-X. Files up to 200 MB.

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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: 677a7b27-8dba-50f8-a903-d3ae3dd1454a

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