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MALPEDIA_Win_Decaf_Auto

autogenerated rule brought to you by yara-signator

MalwareDecafMalpedia 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: Decaf.

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

Summary generated from the rule's metadata and condition.

Rule source

win-decaf-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Decaf_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "688421e5-50f3-54a6-afcf-ed3cc43c3379"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.decaf"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.decaf_auto.yar#L1-L134"
		license_url = "N/A"
		logic_hash = "bc13d1aabe60e36a979a1ab19aaf3f220b675ec157b071ae53bdc10a73fed48d"
		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 = { eb14 488d7818 488b8c2448200000 0f1f00 e8???????? 488b8c24d0050000 48894808 }
		$sequence_1 = { 488d0d69f20800 488908 488d0d02080c00 48890d???????? 833d????????00 7509 488905???????? }
		$sequence_2 = { 488d05ac221c00 bb27000000 e8???????? 488d05f3111c00 bb20000000 e8???????? 48ffc1 }
		$sequence_3 = { e8???????? e8???????? 4889842430110000 48899c2470020000 90 488d050a9d0c00 e8???????? }
		$sequence_4 = { bb19000000 e8???????? 488d053fcd1900 bb1c000000 e8???????? 90 4889442408 }
		$sequence_5 = { e8???????? 488d0554a41400 488b5c2438 488d0d28ff1600 bf07000000 0f1f00 e8???????? }
		$sequence_6 = { 663913 754e 0fb75002 66395302 7544 4889442428 48895c2430 }
		$sequence_7 = { e8???????? 488d3de3581f00 e8???????? e8???????? 48898424f8100000 48899c24200a0000 488b0d???????? }
		$sequence_8 = { c6041ff9 31c9 e9???????? 4983f806 754b 4c8d4301 4c39c6 }
		$sequence_9 = { 488d6c2430 48ba059ac5d4c613bccd 4889542425 48bad4c613bccd3f86c5 4889542428 48ba46f582b1b25cdea7 488954241a }

	condition:
		7 of them and filesize < 7193600
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ eb14 488d7818 488b8c2448200000 0f1f00 e8???????? 488b8c24d0050000 48894808 }
$sequence_1hex{ 488d0d69f20800 488908 488d0d02080c00 48890d???????? 833d????????00 7509 488905???????? }
$sequence_2hex{ 488d05ac221c00 bb27000000 e8???????? 488d05f3111c00 bb20000000 e8???????? 48ffc1 }
$sequence_3hex{ e8???????? e8???????? 4889842430110000 48899c2470020000 90 488d050a9d0c00 e8???????? }
$sequence_4hex{ bb19000000 e8???????? 488d053fcd1900 bb1c000000 e8???????? 90 4889442408 }
$sequence_5hex{ e8???????? 488d0554a41400 488b5c2438 488d0d28ff1600 bf07000000 0f1f00 e8???????? }
$sequence_6hex{ 663913 754e 0fb75002 66395302 7544 4889442428 48895c2430 }
$sequence_7hex{ e8???????? 488d3de3581f00 e8???????? e8???????? 48898424f8100000 48899c24200a0000 488b0d???????? }
$sequence_8hex{ c6041ff9 31c9 e9???????? 4983f806 754b 4c8d4301 4c39c6 }
$sequence_9hex{ 488d6c2430 48ba059ac5d4c613bccd 4889542425 48bad4c613bccd3f86c5 4889542428 48ba46f582b1b25cdea7 488954241a }

Condition

7 of them and filesize < 7193600

In plain words (Heuristic)

  • The file must be smaller than 7193600 (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: 688421e5-50f3-54a6-afcf-ed3cc43c3379

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

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