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MALPEDIA_Win_Mofksys_Auto

autogenerated rule brought to you by yara-signator

MalwareMofksysMalpedia 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: Mofksys.

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

Summary generated from the rule's metadata and condition.

Rule source

win-mofksys-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Mofksys_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "7b88b514-d29d-5b2c-8411-854add715287"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.mofksys"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.mofksys_auto.yar#L1-L132"
		license_url = "N/A"
		logic_hash = "93f0c76a65e16a5a99d9cf00b6b0c0e1ab3763195cea216d67265bdd9c8539ce"
		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 = { 6a00 68???????? 8b0f 51 8d55b4 52 ff15???????? }
		$sequence_1 = { 8b426c 8b4d08 8b516c 8b4010 2b420c 0f80d40a0000 }
		$sequence_2 = { 8bd0 8d4d9c ffd3 8b559c c7459c00000000 6a03 }
		$sequence_3 = { 8d4dc8 ff15???????? 8bd0 b9???????? ff15???????? 8d4dc8 51 }
		$sequence_4 = { 8b952cffffff 6a12 81e20080ffff 66f7da 1bd2 f7da f7da }
		$sequence_5 = { 64892500000000 81ecd8000000 53 56 57 8965ec c745f0c02b4000 }
		$sequence_6 = { 8b8d50ffffff 83c10c ff15???????? 8d4dc0 ff15???????? c745fccc000000 6a01 }
		$sequence_7 = { ffd6 50 68???????? 68???????? ffd7 8bd0 8d4dbc }
		$sequence_8 = { c7459801000000 c7459002000000 ffd3 8bd0 8d4dd4 ffd7 8d4d90 }
		$sequence_9 = { 8b420c 034590 50 8b4dc8 51 8b55d8 52 }

	condition:
		7 of them and filesize < 401408
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 6a00 68???????? 8b0f 51 8d55b4 52 ff15???????? }
$sequence_1hex{ 8b426c 8b4d08 8b516c 8b4010 2b420c 0f80d40a0000 }
$sequence_2hex{ 8bd0 8d4d9c ffd3 8b559c c7459c00000000 6a03 }
$sequence_3hex{ 8d4dc8 ff15???????? 8bd0 b9???????? ff15???????? 8d4dc8 51 }
$sequence_4hex{ 8b952cffffff 6a12 81e20080ffff 66f7da 1bd2 f7da f7da }
$sequence_5hex{ 64892500000000 81ecd8000000 53 56 57 8965ec c745f0c02b4000 }
$sequence_6hex{ 8b8d50ffffff 83c10c ff15???????? 8d4dc0 ff15???????? c745fccc000000 6a01 }
$sequence_7hex{ ffd6 50 68???????? 68???????? ffd7 8bd0 8d4dbc }
$sequence_8hex{ c7459801000000 c7459002000000 ffd3 8bd0 8d4dd4 ffd7 8d4d90 }
$sequence_9hex{ 8b420c 034590 50 8b4dc8 51 8b55d8 52 }

Condition

7 of them and filesize < 401408

In plain words (Heuristic)

  • The file must be smaller than 401408 (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: 7b88b514-d29d-5b2c-8411-854add715287

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