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MALPEDIA_Win_Meow_Auto

autogenerated rule brought to you by yara-signator

MalwareMeowMalpedia 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: Meow.

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

Summary generated from the rule's metadata and condition.

Rule source

win-meow-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Meow_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "b5de81e8-1f44-5e30-8176-d20d508f6961"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.meow"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.meow_auto.yar#L1-L127"
		license_url = "N/A"
		logic_hash = "19192ecf084d89611de05e02f6080f20d3a66cb4fa252b82b0945c52f2f7f8e2"
		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 = { c685eafeffff03 c685ebfeffff7a c685ecfeffff03 c685edfeffff70 c685eefeffff03 c685effeffff04 c685f0feffff03 }
		$sequence_1 = { 8b5df0 2bc3 8b7d30 3bf8 772f 83f908 8d043b }
		$sequence_2 = { 0f434d08 57 8975ec 66837c41fe5c 0f859d000000 c645f800 }
		$sequence_3 = { 8d4d90 c6459000 c645916c c6459205 c645936d }
		$sequence_4 = { 0fb6c0 83e848 8d04c0 99 f7fb 8d427f 99 }
		$sequence_5 = { c685f5f9ffff6d c685f6f9ffff0f c685f7f9ffff5b c685f8f9ffff0f 8d8df0f9ffff c685f9f9ffff0f }
		$sequence_6 = { c68555f8ffff52 c68556f8ffff05 c68557f8ffff63 c68558f8ffff05 c68559f8ffff77 c6855af8ffff05 8d8d50f8ffff }
		$sequence_7 = { c6858ffeffff6c c68590feffff29 c68591feffff0a c68592feffff29 c68593feffff7c }
		$sequence_8 = { c6459b28 c6459c5f c6459d55 c6459e5f c6459f67 c645a05f }
		$sequence_9 = { 7540 33f6 8d7e7f 0f1f4000 0f1f840000000000 8a843545ffffff 0fb6c8 }

	condition:
		7 of them and filesize < 492544
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ c685eafeffff03 c685ebfeffff7a c685ecfeffff03 c685edfeffff70 c685eefeffff03 c685effeffff04 c685f0feffff03 }
$sequence_1hex{ 8b5df0 2bc3 8b7d30 3bf8 772f 83f908 8d043b }
$sequence_2hex{ 0f434d08 57 8975ec 66837c41fe5c 0f859d000000 c645f800 }
$sequence_3hex{ 8d4d90 c6459000 c645916c c6459205 c645936d }
$sequence_4hex{ 0fb6c0 83e848 8d04c0 99 f7fb 8d427f 99 }
$sequence_5hex{ c685f5f9ffff6d c685f6f9ffff0f c685f7f9ffff5b c685f8f9ffff0f 8d8df0f9ffff c685f9f9ffff0f }
$sequence_6hex{ c68555f8ffff52 c68556f8ffff05 c68557f8ffff63 c68558f8ffff05 c68559f8ffff77 c6855af8ffff05 8d8d50f8ffff }
$sequence_7hex{ c6858ffeffff6c c68590feffff29 c68591feffff0a c68592feffff29 c68593feffff7c }
$sequence_8hex{ c6459b28 c6459c5f c6459d55 c6459e5f c6459f67 c645a05f }
$sequence_9hex{ 7540 33f6 8d7e7f 0f1f4000 0f1f840000000000 8a843545ffffff 0fb6c8 }

Condition

7 of them and filesize < 492544

In plain words (Heuristic)

  • The file must be smaller than 492544 (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: b5de81e8-1f44-5e30-8176-d20d508f6961

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