win_fct_auto

YARA detection rule by Felix Bilstein - yara-signator at cocacoding dot com

Detects win.fct.

rule win_fct_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.fct."
        info = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.6.0"
        signator_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.fct"
        malpedia_rule_date = "20260916"
        malpedia_hash = "53a643781c18e08f4a50949af60172d837a0b6f6"
        malpedia_version = "20260917"
        malpedia_license = "CC BY-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    


    strings:
        $sequence_0 = { 3bc8 772f 83fb08 8d0409 50 8d75d8 0f4375d8 }
                                                                                                
        $sequence_1 = { 8b8d74fdffff ebdb 57 ff15???????? c645fc04 33c0 }
                                                                                    
        $sequence_2 = { c745ec8e2d4000 894df8 8945fc 64a100000000 8945e8 8d45e8 64a300000000 }
                                                                                                
        $sequence_3 = { 50 8d45f4 64a300000000 8bf9 89bd0cfdffff 33c0 8d5102 }
                                                                                                
        $sequence_4 = { 0f8495330000 c3 833d????????ff 7503 33c0 c3 53 }
                                                                                                
        $sequence_5 = { 0f8421010000 6683bd80fdffff2e 0f84cf040000 8bcf c745e800000000 33c0 c745ec07000000 }
                                                                                                
        $sequence_6 = { 83c40c 33c0 6689047e eb21 6a04 68???????? c68510fdffff00 }
                                                                                                
        $sequence_7 = { 8b9574fdffff 2b75d4 75dd 33c9 }
                                                            
        $sequence_8 = { 51 57 8d4dbc e8???????? c745fc00000000 8b75d0 8bc6 }
                                                                                                
        $sequence_9 = { 66890437 eb1b 50 51 }
                                                            
    condition:
        7 of them and filesize < 204800
}

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

f9376e73-d393-4b47-a2c6-4a6d888147bc

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

[[ reason ]]

What does this mean?

Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

[[ reason ]]

What do these messages mean?

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

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