rule win_fireball_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.fireball."
        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.fireball"
        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 = { c68424f801000004 6a01 33c0 68???????? 8d4c242c c744244007000000 c744243c00000000 }
            // n = 7, score = 100
            //   c68424f801000004     | mov                 byte ptr [esp + 0x1f8], 4
            //   6a01                 | push                1
            //   33c0                 | xor                 eax, eax
            //   68????????           |                     
            //   8d4c242c             | lea                 ecx, [esp + 0x2c]
            //   c744244007000000     | mov                 dword ptr [esp + 0x40], 7
            //   c744243c00000000     | mov                 dword ptr [esp + 0x3c], 0

        $sequence_1 = { 3de4000000 7309 8b04c558812400 5d c3 33c0 }
            // n = 6, score = 100
            //   3de4000000           | cmp                 eax, 0xe4
            //   7309                 | jae                 0xb
            //   8b04c558812400       | mov                 eax, dword ptr [eax*8 + 0x248158]
            //   5d                   | pop                 ebp
            //   c3                   | ret                 
            //   33c0                 | xor                 eax, eax

        $sequence_2 = { 8bf1 83c9ff 837b10ff 8b5610 0f424b10 83c8ff 2bc2 }
            // n = 7, score = 100
            //   8bf1                 | mov                 esi, ecx
            //   83c9ff               | or                  ecx, 0xffffffff
            //   837b10ff             | cmp                 dword ptr [ebx + 0x10], -1
            //   8b5610               | mov                 edx, dword ptr [esi + 0x10]
            //   0f424b10             | cmovb               ecx, dword ptr [ebx + 0x10]
            //   83c8ff               | or                  eax, 0xffffffff
            //   2bc2                 | sub                 eax, edx

        $sequence_3 = { 8bc1 c1f805 83e11f 8b0485000a2500 c1e106 804c080420 8b4d14 }
            // n = 7, score = 100
            //   8bc1                 | mov                 eax, ecx
            //   c1f805               | sar                 eax, 5
            //   83e11f               | and                 ecx, 0x1f
            //   8b0485000a2500       | mov                 eax, dword ptr [eax*4 + 0x250a00]
            //   c1e106               | shl                 ecx, 6
            //   804c080420           | or                  byte ptr [eax + ecx + 4], 0x20
            //   8b4d14               | mov                 ecx, dword ptr [ebp + 0x14]

        $sequence_4 = { 833cf5a8f5240000 7513 56 e8???????? }
            // n = 4, score = 100
            //   833cf5a8f5240000     | cmp                 dword ptr [esi*8 + 0x24f5a8], 0
            //   7513                 | jne                 0x15
            //   56                   | push                esi
            //   e8????????           |                     

        $sequence_5 = { c68424f801000008 6a01 33c0 68???????? 8d4c2444 }
            // n = 5, score = 100
            //   c68424f801000008     | mov                 byte ptr [esp + 0x1f8], 8
            //   6a01                 | push                1
            //   33c0                 | xor                 eax, eax
            //   68????????           |                     
            //   8d4c2444             | lea                 ecx, [esp + 0x44]

        $sequence_6 = { 833d????????08 ba???????? 0f4315???????? 83ec18 8bf4 33c0 }
            // n = 6, score = 100
            //   833d????????08       |                     
            //   ba????????           |                     
            //   0f4315????????       |                     
            //   83ec18               | sub                 esp, 0x18
            //   8bf4                 | mov                 esi, esp
            //   33c0                 | xor                 eax, eax

        $sequence_7 = { 83fb08 720b ff7508 e8???????? 83c404 8bc6 8b4df4 }
            // n = 7, score = 100
            //   83fb08               | cmp                 ebx, 8
            //   720b                 | jb                  0xd
            //   ff7508               | push                dword ptr [ebp + 8]
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   8bc6                 | mov                 eax, esi
            //   8b4df4               | mov                 ecx, dword ptr [ebp - 0xc]

        $sequence_8 = { 8d45b0 50 8d8538f9ffff 50 8d9558fbffff 8d4dd8 }
            // n = 6, score = 100
            //   8d45b0               | lea                 eax, [ebp - 0x50]
            //   50                   | push                eax
            //   8d8538f9ffff         | lea                 eax, [ebp - 0x6c8]
            //   50                   | push                eax
            //   8d9558fbffff         | lea                 edx, [ebp - 0x4a8]
            //   8d4dd8               | lea                 ecx, [ebp - 0x28]

        $sequence_9 = { 0f43c6 6683044820 8b551c 8b7508 41 }
            // n = 5, score = 100
            //   0f43c6               | cmovae              eax, esi
            //   6683044820           | add                 word ptr [eax + ecx*2], 0x20
            //   8b551c               | mov                 edx, dword ptr [ebp + 0x1c]
            //   8b7508               | mov                 esi, dword ptr [ebp + 8]
            //   41                   | inc                 ecx

    condition:
        7 of them and filesize < 335872
}