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MALPEDIA_Win_Ymir_Auto

autogenerated rule brought to you by yara-signator

MalwareYmirMalpedia 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: Ymir.

It defines 8 patterns (0 text, 8 hex, 0 regex).

Summary generated from the rule's metadata and condition.

Rule source

win-ymir-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Ymir_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "278c6b49-2804-5b51-9c14-eb7f1a9b17c8"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.ymir"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.ymir_auto.yar#L1-L90"
		license_url = "N/A"
		logic_hash = "3d66ab481f8e9eef312301fbcf8dd546d68cce30bc83067a87933ba87376dbb7"
		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 = { 4c89ea 488d4e08 4c8b3d???????? 668986e8000000 }
		$sequence_1 = { 4c89ea 488d4b18 e8???????? 488b05???????? }
		$sequence_2 = { 4c89ea 488d4830 e8???????? 48035c2440 }
		$sequence_3 = { 4c89ea 488d1dde871900 48c784245801000000000000 4c89f1 }
		$sequence_4 = { 4c89ea 488d0df9be2600 48891d???????? e8???????? }
		$sequence_5 = { 4c89ea 488d4e08 48c786e000000000000000 498d4618 }
		$sequence_6 = { 4c89ea 488d4b10 4989e9 ff5048 }
		$sequence_7 = { 4c89ea 488d1dae691900 48c784243801000000000000 4c89f1 }

	condition:
		7 of them and filesize < 5530624
}

Strings (8 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 4c89ea 488d4e08 4c8b3d???????? 668986e8000000 }
$sequence_1hex{ 4c89ea 488d4b18 e8???????? 488b05???????? }
$sequence_2hex{ 4c89ea 488d4830 e8???????? 48035c2440 }
$sequence_3hex{ 4c89ea 488d1dde871900 48c784245801000000000000 4c89f1 }
$sequence_4hex{ 4c89ea 488d0df9be2600 48891d???????? e8???????? }
$sequence_5hex{ 4c89ea 488d4e08 48c786e000000000000000 498d4618 }
$sequence_6hex{ 4c89ea 488d4b10 4989e9 ff5048 }
$sequence_7hex{ 4c89ea 488d1dae691900 48c784243801000000000000 4c89f1 }

Condition

7 of them and filesize < 5530624

In plain words (Heuristic)

  • The file must be smaller than 5530624 (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.

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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: 278c6b49-2804-5b51-9c14-eb7f1a9b17c8

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