win_ascentloader_auto

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

Detects win.ascentloader.

rule win_ascentloader_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.ascentloader."
        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.ascentloader"
        malpedia_rule_date = "20260916"
        malpedia_hash = "53a643781c18e08f4a50949af60172d837a0b6f6"
        malpedia_version = "20260917"
        malpedia_license = "CC BY-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    


    strings:
        $sequence_0 = { b8???????? eb0a b900240000 b8???????? }
                                                            
        $sequence_1 = { 58 6a22 66894586 66898d76ffffff 66894d84 59 }
                                                                                    
        $sequence_2 = { 6a65 58 88442427 33db 8844242d }
                                                                        
        $sequence_3 = { 8b4dfc e8???????? 8b4df8 e8???????? 8b4df4 }
                                                                        
        $sequence_4 = { 8955fc 83b88400000000 0f86ea000000 56 8bb080000000 }
                                                                        
        $sequence_5 = { 53 53 8d45ec 8bf2 50 }
                                                                        
        $sequence_6 = { 57 68000000f0 6a01 33db 894de8 53 }
                                                                                    
        $sequence_7 = { 83f8ff 7518 ff15???????? 57 ff15???????? ff15???????? e9???????? }
                                                                                                
        $sequence_8 = { 53 eb01 56 ff15???????? 6a50 }
                                                                        
        $sequence_9 = { 8b5d10 56 8bf1 81e1ffff0000 c1ee10 83fb01 7531 }
                                                                                                
    condition:
        7 of them and filesize < 253952
}

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

97f851d0-99fc-4383-9115-6ac2b9426684

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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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