rule win_heyoka_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.heyoka."
        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.heyoka"
        malpedia_rule_date = "20260422"
        malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
        malpedia_version = "20260504"
        malpedia_license = "CC BY-SA 4.0"
        malpedia_sharing = "TLP:WHITE"

    /* DISCLAIMER
     * The strings used in this rule have been automatically selected from the
     * disassembly of memory dumps and unpacked files, using YARA-Signator.
     * The code and documentation is published here:
     * https://github.com/fxb-cocacoding/yara-signator
     * As Malpedia is used as data source, please note that for a given
     * number of families, only single samples are documented.
     * This likely impacts the degree of generalization these rules will offer.
     * Take the described generation method also into consideration when you
     * apply the rules in your use cases and assign them confidence levels.
     */


    strings:
        $sequence_0 = { 8b85e4fbffff c6403500 8b8ddcfbffff 83c106 8b95e4fbffff 894a30 c785e0fbffff00000000 }
            // n = 7, score = 100
            //   8b85e4fbffff         | mov                 eax, dword ptr [ebp - 0x41c]
            //   c6403500             | mov                 byte ptr [eax + 0x35], 0
            //   8b8ddcfbffff         | mov                 ecx, dword ptr [ebp - 0x424]
            //   83c106               | add                 ecx, 6
            //   8b95e4fbffff         | mov                 edx, dword ptr [ebp - 0x41c]
            //   894a30               | mov                 dword ptr [edx + 0x30], ecx
            //   c785e0fbffff00000000     | mov    dword ptr [ebp - 0x420], 0

        $sequence_1 = { 8b45f8 81bc906050000000100000 75dd 8b4dfc 8b55f8 8b848a64940000 8b4df8 }
            // n = 7, score = 100
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   81bc906050000000100000     | cmp    dword ptr [eax + edx*4 + 0x5060], 0x1000
            //   75dd                 | jne                 0xffffffdf
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   8b848a64940000       | mov                 eax, dword ptr [edx + ecx*4 + 0x9464]
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]

        $sequence_2 = { 83e030 c1f804 8d0c88 8b55f8 0355f0 880a }
            // n = 6, score = 100
            //   83e030               | and                 eax, 0x30
            //   c1f804               | sar                 eax, 4
            //   8d0c88               | lea                 ecx, [eax + ecx*4]
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   0355f0               | add                 edx, dword ptr [ebp - 0x10]
            //   880a                 | mov                 byte ptr [edx], cl

        $sequence_3 = { 740c 8b55fc 52 8b4de0 e8???????? eba7 837de800 }
            // n = 7, score = 100
            //   740c                 | je                  0xe
            //   8b55fc               | mov                 edx, dword ptr [ebp - 4]
            //   52                   | push                edx
            //   8b4de0               | mov                 ecx, dword ptr [ebp - 0x20]
            //   e8????????           |                     
            //   eba7                 | jmp                 0xffffffa9
            //   837de800             | cmp                 dword ptr [ebp - 0x18], 0

        $sequence_4 = { 52 ff15???????? 25ffff0000 8b4df4 8d54010c 8955f4 8b450c }
            // n = 7, score = 100
            //   52                   | push                edx
            //   ff15????????         |                     
            //   25ffff0000           | and                 eax, 0xffff
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]
            //   8d54010c             | lea                 edx, [ecx + eax + 0xc]
            //   8955f4               | mov                 dword ptr [ebp - 0xc], edx
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]

        $sequence_5 = { 894508 8b4508 c600ff 8b4d08 c78181000000ffffffff 8b5508 c6420100 }
            // n = 7, score = 100
            //   894508               | mov                 dword ptr [ebp + 8], eax
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   c600ff               | mov                 byte ptr [eax], 0xff
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   c78181000000ffffffff     | mov    dword ptr [ecx + 0x81], 0xffffffff
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   c6420100             | mov                 byte ptr [edx + 1], 0

        $sequence_6 = { 8b4d08 51 8b55f8 8b4210 50 e8???????? 83c40c }
            // n = 7, score = 100
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   51                   | push                ecx
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   8b4210               | mov                 eax, dword ptr [edx + 0x10]
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_7 = { 0fbe45ed c1f802 83e007 0bd0 8855f4 0fbe4ded 83e103 }
            // n = 7, score = 100
            //   0fbe45ed             | movsx               eax, byte ptr [ebp - 0x13]
            //   c1f802               | sar                 eax, 2
            //   83e007               | and                 eax, 7
            //   0bd0                 | or                  edx, eax
            //   8855f4               | mov                 byte ptr [ebp - 0xc], dl
            //   0fbe4ded             | movsx               ecx, byte ptr [ebp - 0x13]
            //   83e103               | and                 ecx, 3

        $sequence_8 = { 8b55dc 83c204 52 e8???????? 83c408 8b4514 50 }
            // n = 7, score = 100
            //   8b55dc               | mov                 edx, dword ptr [ebp - 0x24]
            //   83c204               | add                 edx, 4
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   8b4514               | mov                 eax, dword ptr [ebp + 0x14]
            //   50                   | push                eax

        $sequence_9 = { c1e007 0fbe4df1 83e11f c1e102 0bc1 0fbe55f2 c1fa03 }
            // n = 7, score = 100
            //   c1e007               | shl                 eax, 7
            //   0fbe4df1             | movsx               ecx, byte ptr [ebp - 0xf]
            //   83e11f               | and                 ecx, 0x1f
            //   c1e102               | shl                 ecx, 2
            //   0bc1                 | or                  eax, ecx
            //   0fbe55f2             | movsx               edx, byte ptr [ebp - 0xe]
            //   c1fa03               | sar                 edx, 3

    condition:
        7 of them and filesize < 270336
}