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MALPEDIA_Win_Underminer_Ek_Auto

autogenerated rule brought to you by yara-signator

MalwareUnderminer EkMalpedia signator rulesCreative Commons Attribution-ShareAlike 4.0Compiles with YARA-X (with warnings)
Author
Felix Bilstein - yara-signator at cocacoding dot com
Date
2026-05-04
Modified
2026-05-18
Score / Quality
75 / 73

What this rule detects

autogenerated rule brought to you by yara-signator

Associated malware family: Underminer Ek.

It defines 16 patterns (0 text, 16 hex, 0 regex).

YARA-X says: warning[text_as_hex]: hex pattern could be written as text literal

Summary generated from the rule's metadata and condition.

Rule source

win-underminer-ek-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Underminer_Ek_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "478c25cf-e188-5b79-8aeb-6935a8b536f7"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.underminer_ek"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.underminer_ek_auto.yar#L1-L178"
		license_url = "N/A"
		logic_hash = "4786465e315c0c23f824b89be267cb511060061f2cde5a1665c6404f963bc60b"
		score = 75
		quality = 73
		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 = { 8a450f 884708 0fb6450b 89470c e9???????? 3cc8 }
		$sequence_1 = { 3d40420f00 734f 83ec18 8bcc 68???????? e8???????? 8d4dc8 }
		$sequence_2 = { 8904bd582c4300 85c0 7514 6a0c 5e 8975e4 c745fcfeffffff }
		$sequence_3 = { c3 ff742408 8b442408 ff10 c3 }
		$sequence_4 = { 897df8 6681384d5a 0f85bd000000 8b703c 03f0 }
		$sequence_5 = { 6a00 50 ff5604 8d460c 6a00 50 ff16 }
		$sequence_6 = { 0fb6560b c1e008 0bc2 8be8 8d470c 3bc8 7278 }
		$sequence_7 = { 8b75c8 8d4de0 ff75d8 8b55f0 83ff10 0f43c6 }
		$sequence_8 = { 47 884607 897df4 c745f04a50fa7e eb18 3ca0 7214 }
		$sequence_9 = { 8d45e0 50 8d8d08ffffff e8???????? 8b55f4 83fa10 }
		$sequence_10 = { 3bd8 3be2 3bf3 3bf8 }
		$sequence_11 = { 7473 3bc3 c7450c32000000 7538 8b35???????? bf1453fa7e }
		$sequence_12 = { c7431000000000 8d5101 c743140f000000 c60300 0f1f8000000000 8a01 }
		$sequence_13 = { 8b450c 0fb684c848914200 c1e804 c9 c20800 8bff }
		$sequence_14 = { 3836 42 3653 3658 }
		$sequence_15 = { 03c8 3b4de8 7751 395de0 7440 83c00d 50 }

	condition:
		7 of them and filesize < 466944
}

Strings (16 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 8a450f 884708 0fb6450b 89470c e9???????? 3cc8 }
$sequence_1hex{ 3d40420f00 734f 83ec18 8bcc 68???????? e8???????? 8d4dc8 }
$sequence_2hex{ 8904bd582c4300 85c0 7514 6a0c 5e 8975e4 c745fcfeffffff }
$sequence_3hex{ c3 ff742408 8b442408 ff10 c3 }
$sequence_4hex{ 897df8 6681384d5a 0f85bd000000 8b703c 03f0 }
$sequence_5hex{ 6a00 50 ff5604 8d460c 6a00 50 ff16 }
$sequence_6hex{ 0fb6560b c1e008 0bc2 8be8 8d470c 3bc8 7278 }
$sequence_7hex{ 8b75c8 8d4de0 ff75d8 8b55f0 83ff10 0f43c6 }
$sequence_8hex{ 47 884607 897df4 c745f04a50fa7e eb18 3ca0 7214 }
$sequence_9hex{ 8d45e0 50 8d8d08ffffff e8???????? 8b55f4 83fa10 }
$sequence_10hex{ 3bd8 3be2 3bf3 3bf8 }
$sequence_11hex{ 7473 3bc3 c7450c32000000 7538 8b35???????? bf1453fa7e }
$sequence_12hex{ c7431000000000 8d5101 c743140f000000 c60300 0f1f8000000000 8a01 }
$sequence_13hex{ 8b450c 0fb684c848914200 c1e804 c9 c20800 8bff }
$sequence_14hex{ 3836 42 3653 3658 }
$sequence_15hex{ 03c8 3b4de8 7751 395de0 7440 83c00d 50 }

Condition

7 of them and filesize < 466944

In plain words (Heuristic)

  • The file must be smaller than 466944 (a cheap guard that skips large files).
  • At least 7 patterns in the rule must match.

Test this rule in your browser

Drop a file to scan it with this rule using YARA-X compiled to WebAssembly. Nothing is uploaded.

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: 478c25cf-e188-5b79-8aeb-6935a8b536f7

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