YARA · Malpedia signator rules
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:
= "autogenerated rule brought to you by yara-signator"
= "Felix Bilstein - yara-signator at cocacoding dot com"
= "21284a89-8752-54a0-93d5-e4ccc3ab651b"
= "2026-05-04"
= "2026-05-18"
= "https://malpedia.caad.fkie.fraunhofer.de/details/win.sysjoker"
= "https://github.com/malpedia/signator-rules//blob/c901f97b7df03e41917da74c2a84b04c227316c2/rules/win.sysjoker_auto.yar#L1-L134"
= "N/A"
= "c28d70b4383688831fd9414587b1779fa5c5c837f9d11f2190ec7897fa815774"
= 75
= 75
= "FILE"
= "1"
= "yara-signator v0.6.0"
= "callsandjumps;datarefs;binvalue"
= "20260422"
= "a182e35da64e6d71cb55f125c4d4225196523f14"
= "20260504"
= "CC BY-SA 4.0"
= "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)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $sequence_0 | hex | { 0faee8 0fb688e0e04400 83e10f eb02 33c9 8b450c 0fb684c800e14400 } | |
| $sequence_1 | hex | { 7522 6685c9 7415 668b4802 663b4a02 7513 83c004 } | |
| $sequence_2 | hex | { 7202 8b07 c60000 8b4620 894624 8a4e0c 884dbf } | |
| $sequence_3 | hex | { 750d 68???????? 8d4db8 e8???????? 8d45b8 c645fc27 50 } | |
| $sequence_4 | hex | { 8b432c 8b00 85c0 7430 8b7d08 3bc1 8bf1 } | |
| $sequence_5 | hex | { 2bd6 8d4dd4 d1fa 52 50 e8???????? 51 } | |
| $sequence_6 | hex | { 8b55f0 894f18 8b4f24 3b4f18 0f83ad060000 8b4714 46 } | |
| $sequence_7 | hex | { b901000000 2b4afc 2bc6 0bc8 7d0a 56 8bcf } | |
| $sequence_8 | hex | { 83e73f c1f806 6bcf38 8945f4 8b0485c0fc4500 894df0 8a440129 } | |
| $sequence_9 | hex | { c645fc05 50 8d4dbc e8???????? 8b458c 33d2 8b7d98 } |
Condition
7 of them and filesize < 832512In 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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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)
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
| 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 |
Tags:FILE
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