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MALPEDIA_Win_Skinnyboy_Auto

autogenerated rule brought to you by yara-signator

MalwareSkinnyboyMalpedia 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: Skinnyboy.

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

Summary generated from the rule's metadata and condition.

Rule source

win-skinnyboy-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Skinnyboy_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "24a64f43-deef-557c-9fd6-67c28ce40905"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.skinnyboy"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.skinnyboy_auto.yar#L1-L127"
		license_url = "N/A"
		logic_hash = "e1fe3c77c85dc8fb19abbee4d29db040d7e39adcf95610e368b642b3c9a51b2e"
		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 = { 85c0 7403 50 ffd7 ffd3 6a00 }
		$sequence_1 = { 0fb68098b20010 83e00f eb02 33c0 8bbdc4fdffff 6bc009 0fb6bc38b8b20010 }
		$sequence_2 = { 668b444de4 6631444dd0 41 3bca 72f1 33c0 }
		$sequence_3 = { 8d8278040110 8945e4 803800 8bc8 7435 8a4101 84c0 }
		$sequence_4 = { 833cfdd80b011000 7515 68a00f0000 56 ff15???????? }
		$sequence_5 = { 50 ffd6 8b85e0feffff 85c0 7403 50 }
		$sequence_6 = { ffb55cfbffff ff15???????? 85c0 0f85d2feffff ffb55cfbffff ff15???????? ff33 }
		$sequence_7 = { ff15???????? 8bf0 6a01 56 ff15???????? 8d4c2420 51 }
		$sequence_8 = { 7413 8a8c1564feffff 308c15e4feffff 42 3bd0 72ed }
		$sequence_9 = { ff15???????? 8d442430 50 ff15???????? 85c0 742d }

	condition:
		7 of them and filesize < 176128
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 85c0 7403 50 ffd7 ffd3 6a00 }
$sequence_1hex{ 0fb68098b20010 83e00f eb02 33c0 8bbdc4fdffff 6bc009 0fb6bc38b8b20010 }
$sequence_2hex{ 668b444de4 6631444dd0 41 3bca 72f1 33c0 }
$sequence_3hex{ 8d8278040110 8945e4 803800 8bc8 7435 8a4101 84c0 }
$sequence_4hex{ 833cfdd80b011000 7515 68a00f0000 56 ff15???????? }
$sequence_5hex{ 50 ffd6 8b85e0feffff 85c0 7403 50 }
$sequence_6hex{ ffb55cfbffff ff15???????? 85c0 0f85d2feffff ffb55cfbffff ff15???????? ff33 }
$sequence_7hex{ ff15???????? 8bf0 6a01 56 ff15???????? 8d4c2420 51 }
$sequence_8hex{ 7413 8a8c1564feffff 308c15e4feffff 42 3bd0 72ed }
$sequence_9hex{ ff15???????? 8d442430 50 ff15???????? 85c0 742d }

Condition

7 of them and filesize < 176128

In plain words (Heuristic)

  • The file must be smaller than 176128 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

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

Open in editor

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: 24a64f43-deef-557c-9fd6-67c28ce40905

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

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