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MALPEDIA_Win_Sysjoker_Auto

autogenerated rule brought to you by yara-signator

MalwareSysjokerMalpedia 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: Sysjoker.

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

Summary generated from the rule's metadata and condition.

Rule source

win-sysjoker-auto.yarCreative Commons Attribution-ShareAlike 4.0
rule MALPEDIA_Win_Sysjoker_Auto : FILE
{
	meta:
		description = "autogenerated rule brought to you by yara-signator"
		author = "Felix Bilstein - yara-signator at cocacoding dot com"
		id = "21284a89-8752-54a0-93d5-e4ccc3ab651b"
		date = "2026-05-04"
		modified = "2026-05-18"
		reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.sysjoker"
		source_url = "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.sysjoker_auto.yar#L1-L134"
		license_url = "N/A"
		logic_hash = "c28d70b4383688831fd9414587b1779fa5c5c837f9d11f2190ec7897fa815774"
		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 = { 0faee8 0fb688e0e04400 83e10f eb02 33c9 8b450c 0fb684c800e14400 }
		$sequence_1 = { 7522 6685c9 7415 668b4802 663b4a02 7513 83c004 }
		$sequence_2 = { 7202 8b07 c60000 8b4620 894624 8a4e0c 884dbf }
		$sequence_3 = { 750d 68???????? 8d4db8 e8???????? 8d45b8 c645fc27 50 }
		$sequence_4 = { 8b432c 8b00 85c0 7430 8b7d08 3bc1 8bf1 }
		$sequence_5 = { 2bd6 8d4dd4 d1fa 52 50 e8???????? 51 }
		$sequence_6 = { 8b55f0 894f18 8b4f24 3b4f18 0f83ad060000 8b4714 46 }
		$sequence_7 = { b901000000 2b4afc 2bc6 0bc8 7d0a 56 8bcf }
		$sequence_8 = { 83e73f c1f806 6bcf38 8945f4 8b0485c0fc4500 894df0 8a440129 }
		$sequence_9 = { c645fc05 50 8d4dbc e8???????? 8b458c 33d2 8b7d98 }

	condition:
		7 of them and filesize < 832512
}

Strings (10 patterns)

IdentifierTypeValueModifiers
$sequence_0hex{ 0faee8 0fb688e0e04400 83e10f eb02 33c9 8b450c 0fb684c800e14400 }
$sequence_1hex{ 7522 6685c9 7415 668b4802 663b4a02 7513 83c004 }
$sequence_2hex{ 7202 8b07 c60000 8b4620 894624 8a4e0c 884dbf }
$sequence_3hex{ 750d 68???????? 8d4db8 e8???????? 8d45b8 c645fc27 50 }
$sequence_4hex{ 8b432c 8b00 85c0 7430 8b7d08 3bc1 8bf1 }
$sequence_5hex{ 2bd6 8d4dd4 d1fa 52 50 e8???????? 51 }
$sequence_6hex{ 8b55f0 894f18 8b4f24 3b4f18 0f83ad060000 8b4714 46 }
$sequence_7hex{ b901000000 2b4afc 2bc6 0bc8 7d0a 56 8bcf }
$sequence_8hex{ 83e73f c1f806 6bcf38 8945f4 8b0485c0fc4500 894df0 8a440129 }
$sequence_9hex{ c645fc05 50 8d4dbc e8???????? 8b458c 33d2 8b7d98 }

Condition

7 of them and filesize < 832512

In plain words (Heuristic)

  • The file must be smaller than 832512 (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: 21284a89-8752-54a0-93d5-e4ccc3ab651b

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