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MALPEDIA_Win_Medusalocker_Auto

autogenerated rule brought to you by yara-signator

MalwareMedusalockerMalpedia 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: Medusalocker.

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

Summary generated from the rule's metadata and condition.

Rule source

win-medusalocker-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Medusalocker_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "0b72d66d-a4ee-5c7f-bfd5-1998b487f49b"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.medusalocker"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.medusalocker_auto.yar#L1-L125"
		license_url = "N/A"
		logic_hash = "ce714b574ed071a3b22689fee9f7dd0fa05c9e6aa02bec727f2d694ccfe22836"
		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 = { 7419 6a00 8b45fc 8b480c 51 }
		$sequence_1 = { 83c10c e8???????? c745fcffffffff 8d4de4 e8???????? 8b4df4 64890d00000000 }
		$sequence_2 = { 8b4514 50 e8???????? 83c404 50 8bcf }
		$sequence_3 = { 6a00 8b4df8 83c108 51 ff15???????? }
		$sequence_4 = { 894dc0 837dc01a 0f83a7000000 0fb755c0 }
		$sequence_5 = { 51 8d4d08 e8???????? 83f808 7409 c745fc01000000 eb07 }
		$sequence_6 = { 51 894dfc 68???????? 8b4d08 e8???????? 0fb6c0 85c0 }
		$sequence_7 = { e8???????? 8945f8 8b45f8 8b4d08 3b4814 774a }
		$sequence_8 = { 8b8d5cffffff e8???????? 8d55d8 899550ffffff 8b8d50ffffff e8???????? 898560ffffff }
		$sequence_9 = { e8???????? 83c408 8b00 8945c4 8d4dca 51 8d55d0 }

	condition:
		7 of them and filesize < 1433600
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 7419 6a00 8b45fc 8b480c 51 }
$sequence_1hex{ 83c10c e8???????? c745fcffffffff 8d4de4 e8???????? 8b4df4 64890d00000000 }
$sequence_2hex{ 8b4514 50 e8???????? 83c404 50 8bcf }
$sequence_3hex{ 6a00 8b4df8 83c108 51 ff15???????? }
$sequence_4hex{ 894dc0 837dc01a 0f83a7000000 0fb755c0 }
$sequence_5hex{ 51 8d4d08 e8???????? 83f808 7409 c745fc01000000 eb07 }
$sequence_6hex{ 51 894dfc 68???????? 8b4d08 e8???????? 0fb6c0 85c0 }
$sequence_7hex{ e8???????? 8945f8 8b45f8 8b4d08 3b4814 774a }
$sequence_8hex{ 8b8d5cffffff e8???????? 8d55d8 899550ffffff 8b8d50ffffff e8???????? 898560ffffff }
$sequence_9hex{ e8???????? 83c408 8b00 8945c4 8d4dca 51 8d55d0 }

Condition

7 of them and filesize < 1433600

In plain words (Heuristic)

  • The file must be smaller than 1433600 (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: 0b72d66d-a4ee-5c7f-bfd5-1998b487f49b

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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