rule win_vermilion_strike_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.vermilion_strike."
        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.vermilion_strike"
        malpedia_rule_date = "20260916"
        malpedia_hash = "53a643781c18e08f4a50949af60172d837a0b6f6"
        malpedia_version = "20260917"
        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 = { 8bc3 83ec20 8d5001 8a08 40 84c9 }
            // n = 6, score = 200
            //   8bc3                 | mov                 eax, ebx
            //   83ec20               | sub                 esp, 0x20
            //   8d5001               | lea                 edx, [eax + 1]
            //   8a08                 | mov                 cl, byte ptr [eax]
            //   40                   | inc                 eax
            //   84c9                 | test                cl, cl

        $sequence_1 = { 8b4804 8b441908 03cb 83c801 83792800 7503 }
            // n = 6, score = 200
            //   8b4804               | mov                 ecx, dword ptr [eax + 4]
            //   8b441908             | mov                 eax, dword ptr [ecx + ebx + 8]
            //   03cb                 | add                 ecx, ebx
            //   83c801               | or                  eax, 1
            //   83792800             | cmp                 dword ptr [ecx + 0x28], 0
            //   7503                 | jne                 5

        $sequence_2 = { c644242200 c644242313 8b442420 bb10000000 83c40c 8906 8b442420 }
            // n = 7, score = 200
            //   c644242200           | mov                 byte ptr [esp + 0x22], 0
            //   c644242313           | mov                 byte ptr [esp + 0x23], 0x13
            //   8b442420             | mov                 eax, dword ptr [esp + 0x20]
            //   bb10000000           | mov                 ebx, 0x10
            //   83c40c               | add                 esp, 0xc
            //   8906                 | mov                 dword ptr [esi], eax
            //   8b442420             | mov                 eax, dword ptr [esp + 0x20]

        $sequence_3 = { 83c508 e9???????? 83f802 7508 83c50a e9???????? 83f803 }
            // n = 7, score = 200
            //   83c508               | add                 ebp, 8
            //   e9????????           |                     
            //   83f802               | cmp                 eax, 2
            //   7508                 | jne                 0xa
            //   83c50a               | add                 ebp, 0xa
            //   e9????????           |                     
            //   83f803               | cmp                 eax, 3

        $sequence_4 = { 8818 e9???????? 8d4504 8818 e9???????? 8d4504 56 }
            // n = 7, score = 200
            //   8818                 | mov                 byte ptr [eax], bl
            //   e9????????           |                     
            //   8d4504               | lea                 eax, [ebp + 4]
            //   8818                 | mov                 byte ptr [eax], bl
            //   e9????????           |                     
            //   8d4504               | lea                 eax, [ebp + 4]
            //   56                   | push                esi

        $sequence_5 = { 8d6c245c 8b442440 395c2454 7304 }
            // n = 4, score = 200
            //   8d6c245c             | lea                 ebp, [esp + 0x5c]
            //   8b442440             | mov                 eax, dword ptr [esp + 0x40]
            //   395c2454             | cmp                 dword ptr [esp + 0x54], ebx
            //   7304                 | jae                 6

        $sequence_6 = { ffd0 eb08 8b02 50 e8???????? 83c404 834e4801 }
            // n = 7, score = 200
            //   ffd0                 | call                eax
            //   eb08                 | jmp                 0xa
            //   8b02                 | mov                 eax, dword ptr [edx]
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   834e4801             | or                  dword ptr [esi + 0x48], 1

        $sequence_7 = { 33ff 8be8 57 55 e8???????? 83c40c 6a58 }
            // n = 7, score = 200
            //   33ff                 | xor                 edi, edi
            //   8be8                 | mov                 ebp, eax
            //   57                   | push                edi
            //   55                   | push                ebp
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc
            //   6a58                 | push                0x58

        $sequence_8 = { 720c 8b4644 50 e8???????? 83c404 53 33db }
            // n = 7, score = 200
            //   720c                 | jb                  0xe
            //   8b4644               | mov                 eax, dword ptr [esi + 0x44]
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   53                   | push                ebx
            //   33db                 | xor                 ebx, ebx

        $sequence_9 = { 39b42480000000 720d 8b54246c 52 e8???????? 83c404 8bc5 }
            // n = 7, score = 200
            //   39b42480000000       | cmp                 dword ptr [esp + 0x80], esi
            //   720d                 | jb                  0xf
            //   8b54246c             | mov                 edx, dword ptr [esp + 0x6c]
            //   52                   | push                edx
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   8bc5                 | mov                 eax, ebp

    condition:
        7 of them and filesize < 540672
}