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MALPEDIA_Win_Cur1_Downloader_Auto

autogenerated rule brought to you by yara-signator

MalwareCur1 DownloaderMalpedia 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: Cur1 Downloader.

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

Summary generated from the rule's metadata and condition.

Rule source

win-cur1-downloader-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Cur1_Downloader_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "9711944b-1c2e-5261-8908-a67f06a6fed7"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.cur1_downloader"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.cur1_downloader_auto.yar#L1-L125"
		license_url = "N/A"
		logic_hash = "6592bb1b73c68eb722ff838e515bc632ed31472101cdddf4635e60e41a4a016d"
		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 = { 488bc1 4889842498000000 488b442460 4883c008 4889442458 }
		$sequence_1 = { c68424b402000061 c68424b502000064 c68424b602000045 c68424b702000078 c68424b802000000 }
		$sequence_2 = { ff15???????? 488905???????? 488d9424b0030000 488b4c2420 ff15???????? 488905???????? 488d942468030000 }
		$sequence_3 = { c684243801000065 c684243901000079 c684243a01000045 c684243b01000078 c684243c01000057 }
		$sequence_4 = { 488b9424d0000000 488d8c2498000000 e8???????? 488d8c24d0010000 e8???????? 90 488d8c2438010000 }
		$sequence_5 = { c684241d0200006e c684241e02000065 c684241f02000074 c684242002000052 c684242102000065 c684242202000061 }
		$sequence_6 = { 8b8c2468010000 e8???????? 4889442430 c744242040000000 488d442420 4889442428 4c8b442428 }
		$sequence_7 = { c684245502000073 c684245602000074 c684245702000041 c684245802000000 c684242003000049 }
		$sequence_8 = { 41b804010000 488d942400030000 33c9 ff15???????? c744245801000000 e8???????? 833d????????01 }
		$sequence_9 = { c68424a101000072 c68424a201000065 c68424a301000061 c68424a401000074 c68424a501000065 c68424a601000050 c68424a701000072 }

	condition:
		7 of them and filesize < 402432
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 488bc1 4889842498000000 488b442460 4883c008 4889442458 }
$sequence_1hex{ c68424b402000061 c68424b502000064 c68424b602000045 c68424b702000078 c68424b802000000 }
$sequence_2hex{ ff15???????? 488905???????? 488d9424b0030000 488b4c2420 ff15???????? 488905???????? 488d942468030000 }
$sequence_3hex{ c684243801000065 c684243901000079 c684243a01000045 c684243b01000078 c684243c01000057 }
$sequence_4hex{ 488b9424d0000000 488d8c2498000000 e8???????? 488d8c24d0010000 e8???????? 90 488d8c2438010000 }
$sequence_5hex{ c684241d0200006e c684241e02000065 c684241f02000074 c684242002000052 c684242102000065 c684242202000061 }
$sequence_6hex{ 8b8c2468010000 e8???????? 4889442430 c744242040000000 488d442420 4889442428 4c8b442428 }
$sequence_7hex{ c684245502000073 c684245602000074 c684245702000041 c684245802000000 c684242003000049 }
$sequence_8hex{ 41b804010000 488d942400030000 33c9 ff15???????? c744245801000000 e8???????? 833d????????01 }
$sequence_9hex{ c68424a101000072 c68424a201000065 c68424a301000061 c68424a401000074 c68424a501000065 c68424a601000050 c68424a701000072 }

Condition

7 of them and filesize < 402432

In plain words (Heuristic)

  • The file must be smaller than 402432 (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: 9711944b-1c2e-5261-8908-a67f06a6fed7

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