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MALPEDIA_Win_Merdoor_Auto

autogenerated rule brought to you by yara-signator

MalwareMerdoorMalpedia 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: Merdoor.

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

Summary generated from the rule's metadata and condition.

Rule source

win-merdoor-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Merdoor_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "ce97ad18-dd6a-5d38-b1cb-6f602f074318"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.merdoor"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.merdoor_auto.yar#L1-L125"
		license_url = "N/A"
		logic_hash = "f624f566a05578274e6d537f288d926b01192f8176e72a7f99468f16d9fee3ea"
		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 = { c787e802000000000000 e8???????? 8987e4020000 c645fc02 }
		$sequence_1 = { 50 ff7608 ffd7 8986f8000000 83befc00000000 750f 8d45d0 }
		$sequence_2 = { 8d85e6fdffff 50 c785bcfdffff00000000 c785c0fdffff00000000 e8???????? 33c0 }
		$sequence_3 = { 8987b4020000 8d45c0 50 6a00 57 68???????? 6a00 }
		$sequence_4 = { 84c0 75f9 2bca 51 8d8598fcffff }
		$sequence_5 = { 8b5514 8b5d08 c745fc00000000 83790400 8955e0 8955d8 }
		$sequence_6 = { 8bd8 894df8 8bd3 8b4b04 80790d00 7518 }
		$sequence_7 = { c1e706 8b0485f0070210 83c00c 03c7 50 ff15???????? 33c0 }
		$sequence_8 = { 8987b0020000 8d45f0 50 8d45a0 50 ff15???????? 50 }
		$sequence_9 = { ffd6 89858cfdffff 8d45c0 50 57 ffd6 }

	condition:
		7 of them and filesize < 307200
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ c787e802000000000000 e8???????? 8987e4020000 c645fc02 }
$sequence_1hex{ 50 ff7608 ffd7 8986f8000000 83befc00000000 750f 8d45d0 }
$sequence_2hex{ 8d85e6fdffff 50 c785bcfdffff00000000 c785c0fdffff00000000 e8???????? 33c0 }
$sequence_3hex{ 8987b4020000 8d45c0 50 6a00 57 68???????? 6a00 }
$sequence_4hex{ 84c0 75f9 2bca 51 8d8598fcffff }
$sequence_5hex{ 8b5514 8b5d08 c745fc00000000 83790400 8955e0 8955d8 }
$sequence_6hex{ 8bd8 894df8 8bd3 8b4b04 80790d00 7518 }
$sequence_7hex{ c1e706 8b0485f0070210 83c00c 03c7 50 ff15???????? 33c0 }
$sequence_8hex{ 8987b0020000 8d45f0 50 8d45a0 50 ff15???????? 50 }
$sequence_9hex{ ffd6 89858cfdffff 8d45c0 50 57 ffd6 }

Condition

7 of them and filesize < 307200

In plain words (Heuristic)

  • The file must be smaller than 307200 (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.

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: ce97ad18-dd6a-5d38-b1cb-6f602f074318

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