win_mespinoza_auto

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

Detects win.mespinoza.

rule win_mespinoza_auto {

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

    


    strings:
        $sequence_0 = { ff75ec c645fc05 57 ff7518 ff75f0 53 }
                                                                                    
        $sequence_1 = { c745640c000000 e8???????? 8d4d4c c745fc09000000 51 50 8d45dc }
                                                                                                
        $sequence_2 = { 3bd0 0f8c32010000 8b85bcebffff 7f08 3bc7 0f8620010000 8bbdc4ebffff }
                                                                                                
        $sequence_3 = { 0f8620010000 8bbdc4ebffff 85c9 0f88f5000000 8bc1 99 8985c4ebffff }
                                                                                                
        $sequence_4 = { e8???????? c6451700 eb47 85d2 741f 8b07 8d4d9c }
                                                                                                
        $sequence_5 = { 85f6 7438 81feffffff3f 7738 57 56 e8???????? }
                                                                                                
        $sequence_6 = { 0f45c8 894dd4 3bcf 740a 807df300 7504 32d2 }
                                                                                                
        $sequence_7 = { 8d45f4 64a300000000 8bf1 8b4d08 8d45c4 50 e8???????? }
                                                                                                
        $sequence_8 = { c21400 55 8bec 51 56 ff7508 8bf1 }
                                                                                                
        $sequence_9 = { c745fc06000000 0f43ca 8b55f0 8bfa }
                                                            
    condition:
        7 of them and filesize < 1091584
}

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

7ce83887-09cc-44f6-964a-c290866a2ddc

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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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