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MALPEDIA_Win_Montysthree_Auto

autogenerated rule brought to you by yara-signator

MalwareMontysthreeMalpedia 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: Montysthree.

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

Summary generated from the rule's metadata and condition.

Rule source

win-montysthree-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Montysthree_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "74ddc35e-cbc4-5b52-af4b-1976c78265e5"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.montysthree"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.montysthree_auto.yar#L1-L119"
		license_url = "N/A"
		logic_hash = "20b706b4eca6d5b02e478c400a2f0e804bf70ec4650a3c31a417eee1e6747a48"
		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 = { 8d4dec e8???????? 50 68???????? e8???????? 8d45dc 50 }
		$sequence_1 = { 49 49 85c0 7def 83c8ff 5e }
		$sequence_2 = { e8???????? 8d4d28 e8???????? ff455c 8d8578fdffff 50 }
		$sequence_3 = { 68???????? e8???????? 83c410 397d08 }
		$sequence_4 = { e8???????? 59 8b45e8 894608 8b45f8 }
		$sequence_5 = { eb13 57 e8???????? 53 8d4de4 }
		$sequence_6 = { 7409 ff7558 ff15???????? 8b4564 f7d8 1bc0 25???????? }
		$sequence_7 = { 8d45d4 50 8d4de4 e8???????? 8d4de4 e8???????? }
		$sequence_8 = { 8b4520 394709 7407 c7453c01000000 }
		$sequence_9 = { 6aff 6a01 6a01 ff75f0 8d4d08 }

	condition:
		7 of them and filesize < 458752
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 8d4dec e8???????? 50 68???????? e8???????? 8d45dc 50 }
$sequence_1hex{ 49 49 85c0 7def 83c8ff 5e }
$sequence_2hex{ e8???????? 8d4d28 e8???????? ff455c 8d8578fdffff 50 }
$sequence_3hex{ 68???????? e8???????? 83c410 397d08 }
$sequence_4hex{ e8???????? 59 8b45e8 894608 8b45f8 }
$sequence_5hex{ eb13 57 e8???????? 53 8d4de4 }
$sequence_6hex{ 7409 ff7558 ff15???????? 8b4564 f7d8 1bc0 25???????? }
$sequence_7hex{ 8d45d4 50 8d4de4 e8???????? 8d4de4 e8???????? }
$sequence_8hex{ 8b4520 394709 7407 c7453c01000000 }
$sequence_9hex{ 6aff 6a01 6a01 ff75f0 8d4d08 }

Condition

7 of them and filesize < 458752

In plain words (Heuristic)

  • The file must be smaller than 458752 (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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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: 74ddc35e-cbc4-5b52-af4b-1976c78265e5

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