rule win_winmm_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-04-08"
        version = "1"
        description = "Detects win.winmm."
        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.winmm"
        malpedia_rule_date = "20220405"
        malpedia_hash = "ecd38294bd47d5589be5cd5490dc8bb4804afc2a"
        malpedia_version = "20220411"
        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 = { e8???????? 83c40c 85c0 752d 83c606 c744241400000400 eb4f }
            // n = 7, score = 200
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   85c0                 | test                eax, eax
            //   752d                 | jne                 0x2f
            //   83c606               | add                 esi, 6
            //   c744241400000400     | mov                 dword ptr [esp + 0x14], 0x40000
            //   eb4f                 | jmp                 0x51

        $sequence_1 = { 8b4df0 83c104 e9???????? 8b4df0 81c1980c0000 }
            // n = 5, score = 200
            //   8b4df0               | mov                 ecx, dword ptr [ebp - 0x10]
            //   83c104               | add                 ecx, 4
            //   e9????????           |                     
            //   8b4df0               | mov                 ecx, dword ptr [ebp - 0x10]
            //   81c1980c0000         | add                 ecx, 0xc98

        $sequence_2 = { c3 b9???????? e9???????? b8???????? e8???????? 51 6878010000 }
            // n = 7, score = 200
            //   c3                   | ret                 
            //   b9????????           |                     
            //   e9????????           |                     
            //   b8????????           |                     
            //   e8????????           |                     
            //   51                   | push                ecx
            //   6878010000           | push                0x178

        $sequence_3 = { 016c2410 eb29 663d2a00 750b }
            // n = 4, score = 200
            //   016c2410             | add                 dword ptr [esp + 0x10], ebp
            //   eb29                 | jmp                 0x2b
            //   663d2a00             | cmp                 ax, 0x2a
            //   750b                 | jne                 0xd

        $sequence_4 = { ff442410 46 46 66833e00 }
            // n = 4, score = 200
            //   ff442410             | inc                 dword ptr [esp + 0x10]
            //   46                   | inc                 esi
            //   46                   | inc                 esi
            //   66833e00             | cmp                 word ptr [esi], 0

        $sequence_5 = { b9???????? e9???????? c3 b8???????? e8???????? 51 6a3c }
            // n = 7, score = 200
            //   b9????????           |                     
            //   e9????????           |                     
            //   c3                   | ret                 
            //   b8????????           |                     
            //   e8????????           |                     
            //   51                   | push                ecx
            //   6a3c                 | push                0x3c

        $sequence_6 = { 33ff 663bc7 897c2428 7446 }
            // n = 4, score = 200
            //   33ff                 | xor                 edi, edi
            //   663bc7               | cmp                 ax, di
            //   897c2428             | mov                 dword ptr [esp + 0x28], edi
            //   7446                 | je                  0x48

        $sequence_7 = { 33d2 c3 55 8bec 56 ff7514 e8???????? }
            // n = 7, score = 200
            //   33d2                 | xor                 edx, edx
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   56                   | push                esi
            //   ff7514               | push                dword ptr [ebp + 0x14]
            //   e8????????           |                     

        $sequence_8 = { 56 57 8b703c 03f0 56 }
            // n = 5, score = 200
            //   56                   | push                esi
            //   57                   | push                edi
            //   8b703c               | mov                 esi, dword ptr [eax + 0x3c]
            //   03f0                 | add                 esi, eax
            //   56                   | push                esi

        $sequence_9 = { 85ff 0f8449ffffff 85ed 7406 3bfd 7c02 8bfd }
            // n = 7, score = 200
            //   85ff                 | test                edi, edi
            //   0f8449ffffff         | je                  0xffffff4f
            //   85ed                 | test                ebp, ebp
            //   7406                 | je                  8
            //   3bfd                 | cmp                 edi, ebp
            //   7c02                 | jl                  4
            //   8bfd                 | mov                 edi, ebp

    condition:
        7 of them and filesize < 278528
}