win_cmstar_auto

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

Detects win.cmstar.

rule win_cmstar_auto {

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

    


    strings:
        $sequence_0 = { 8b4dec c1e802 6a04 52 8d0481 50 }
                                                                                    
        $sequence_1 = { 53 56 bb04010000 57 53 }
                                                                        
        $sequence_2 = { 8b45d8 836dfc10 ff75fc 8945e0 }
                                                            
        $sequence_3 = { ff75e0 ff30 e8???????? 8b4df8 }
                                                            
        $sequence_4 = { ff75fc 8945e0 8b45dc 83c310 8945e4 }
                                                                        
        $sequence_5 = { ff15???????? 6a04 e8???????? be00040000 }
                                                            
        $sequence_6 = { 85c0 7504 6a03 eb0d 803b4d }
                                                                        
        $sequence_7 = { ff15???????? 8bc6 e9???????? 6a10 8d45d0 }
                                                                        
        $sequence_8 = { 33f6 66ab aa 8bdd 8d442414 33c9 2bd8 }
                                                                                                
        $sequence_9 = { 50 6800280000 55 51 ff15???????? }
                                                                        
        $sequence_10 = { c74424303c000000 c744244400010000 894c2454 8954245c c744246024080000 7505 a1???????? }
                                                                                                
        $sequence_11 = { 49 741e 8a441420 bf???????? 888274420010 83c9ff 33c0 }
                                                                                                
        $sequence_12 = { 53 53 53 68???????? ff15???????? 89442414 }
                                                                                    
        $sequence_13 = { 41 3bcb 7cea 03f3 47 81fe???????? }
                                                                                    
        $sequence_14 = { 83c9ff f2ae f7d1 49 8bfa 8bf2 }
                                                                                    
        $sequence_15 = { 892d???????? 881c28 8d8c24e4120000 8d54246c 51 68???????? 52 }
                                                                                                
    condition:
        7 of them and filesize < 4268032
}

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

9c2425c0-be68-47e7-971c-a3fc1c3c5c88

Propose edits, view related rules, and engage with the community through comments.

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 ]]

Community Discussion