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MALPEDIA_Win_Downex_Auto

autogenerated rule brought to you by yara-signator

MalwareDownexMalpedia 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: Downex.

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

Summary generated from the rule's metadata and condition.

Rule source

win-downex-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Downex_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "75a4c5a4-828c-538a-84fc-d73a146dfd41"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.downex"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.downex_auto.yar#L1-L134"
		license_url = "N/A"
		logic_hash = "c2d8d6f74a78cee1a1b4955dcfce1bba7077f6919a6bd08030ecc79c5f31e95e"
		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 = { ff4014 83c2f0 66d3ef 8b88bc160000 6689b8b8160000 03ca e9???????? }
		$sequence_1 = { e8???????? 83c410 85c0 746a 57 e8???????? 52 }
		$sequence_2 = { 8d8d20feffff e8???????? 8d8d08feffff e8???????? 8b8d10ffffff 83f910 7251 }
		$sequence_3 = { 8901 83f804 7e7b e8???????? 8b30 eb72 39b1a8000000 }
		$sequence_4 = { ffb5f8fdffff e8???????? 8d85ecfdffff 50 e8???????? 83c410 b8e2ffffff }
		$sequence_5 = { d3e0 837d0801 8945a0 c7458cffffffff 8d48ff 894d88 0f85a5000000 }
		$sequence_6 = { ffd7 85c0 75a2 ba???????? b9???????? e8???????? 837c243c10 }
		$sequence_7 = { 898ddcfeffff 8bc7 81f900100000 721a 83c123 898ddcfeffff 8b78fc }
		$sequence_8 = { ff75f8 51 8bcf e8???????? 8b4df4 83f910 7228 }
		$sequence_9 = { 8d45f0 50 e8???????? 83c410 eb1f 81e7ffffdfff f7c200002000 }

	condition:
		7 of them and filesize < 1067008
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ ff4014 83c2f0 66d3ef 8b88bc160000 6689b8b8160000 03ca e9???????? }
$sequence_1hex{ e8???????? 83c410 85c0 746a 57 e8???????? 52 }
$sequence_2hex{ 8d8d20feffff e8???????? 8d8d08feffff e8???????? 8b8d10ffffff 83f910 7251 }
$sequence_3hex{ 8901 83f804 7e7b e8???????? 8b30 eb72 39b1a8000000 }
$sequence_4hex{ ffb5f8fdffff e8???????? 8d85ecfdffff 50 e8???????? 83c410 b8e2ffffff }
$sequence_5hex{ d3e0 837d0801 8945a0 c7458cffffffff 8d48ff 894d88 0f85a5000000 }
$sequence_6hex{ ffd7 85c0 75a2 ba???????? b9???????? e8???????? 837c243c10 }
$sequence_7hex{ 898ddcfeffff 8bc7 81f900100000 721a 83c123 898ddcfeffff 8b78fc }
$sequence_8hex{ ff75f8 51 8bcf e8???????? 8b4df4 83f910 7228 }
$sequence_9hex{ 8d45f0 50 e8???????? 83c410 eb1f 81e7ffffdfff f7c200002000 }

Condition

7 of them and filesize < 1067008

In plain words (Heuristic)

  • The file must be smaller than 1067008 (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: 75a4c5a4-828c-538a-84fc-d73a146dfd41

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