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MALPEDIA_Win_Koobface_Auto

autogenerated rule brought to you by yara-signator

MalwareKoobfaceMalpedia 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: Koobface.

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

Summary generated from the rule's metadata and condition.

Rule source

win-koobface-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Koobface_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "c7c8ac2b-27e8-5e1a-9981-867addc45abf"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.koobface"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.koobface_auto.yar#L1-L127"
		license_url = "N/A"
		logic_hash = "129b7af91c58c9077cd85117dcfa9c5b55737107a489f23dd03d3a620ffd3880"
		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 = { 03048da0534200 eb02 8bc2 f6402480 0f8571ffffff 33f6 }
		$sequence_1 = { 50 c645fc1e e8???????? 56 8945b4 e8???????? 59 }
		$sequence_2 = { 754c 8d8540c1ffff 6a41 50 e8???????? 59 }
		$sequence_3 = { 6a02 8985d4c1ffff ff15???????? 8bd8 83ceff 899d84bfffff 3bde }
		$sequence_4 = { 55 8bec 8b450c 832000 33c0 40 5d }
		$sequence_5 = { 8d3402 56 e8???????? 56 8d45b4 50 8d4d94 }
		$sequence_6 = { 8d8528ffffff 68???????? 50 e8???????? 83c40c 8d8528ffffff 50 }
		$sequence_7 = { e8???????? c3 55 8bec ff7510 ff750c e8???????? }
		$sequence_8 = { 3d???????? 72f1 5d c3 0fb611 }
		$sequence_9 = { 57 c645fc04 ff5124 ff7508 }

	condition:
		7 of them and filesize < 368640
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 03048da0534200 eb02 8bc2 f6402480 0f8571ffffff 33f6 }
$sequence_1hex{ 50 c645fc1e e8???????? 56 8945b4 e8???????? 59 }
$sequence_2hex{ 754c 8d8540c1ffff 6a41 50 e8???????? 59 }
$sequence_3hex{ 6a02 8985d4c1ffff ff15???????? 8bd8 83ceff 899d84bfffff 3bde }
$sequence_4hex{ 55 8bec 8b450c 832000 33c0 40 5d }
$sequence_5hex{ 8d3402 56 e8???????? 56 8d45b4 50 8d4d94 }
$sequence_6hex{ 8d8528ffffff 68???????? 50 e8???????? 83c40c 8d8528ffffff 50 }
$sequence_7hex{ e8???????? c3 55 8bec ff7510 ff750c e8???????? }
$sequence_8hex{ 3d???????? 72f1 5d c3 0fb611 }
$sequence_9hex{ 57 c645fc04 ff5124 ff7508 }

Condition

7 of them and filesize < 368640

In plain words (Heuristic)

  • The file must be smaller than 368640 (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: c7c8ac2b-27e8-5e1a-9981-867addc45abf

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