rule win_lowball_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.lowball."
        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.lowball"
        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 = { 8b2d???????? 83c9ff bf???????? 33c0 8d542418 f2ae }
            // n = 6, score = 100
            //   8b2d????????         |                     
            //   83c9ff               | or                  ecx, 0xffffffff
            //   bf????????           |                     
            //   33c0                 | xor                 eax, eax
            //   8d542418             | lea                 edx, [esp + 0x18]
            //   f2ae                 | repne scasb         al, byte ptr es:[edi]

        $sequence_1 = { 4f c1e902 f3a5 8bcb 8d84242c040000 83e103 }
            // n = 6, score = 100
            //   4f                   | dec                 edi
            //   c1e902               | shr                 ecx, 2
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   8bcb                 | mov                 ecx, ebx
            //   8d84242c040000       | lea                 eax, [esp + 0x42c]
            //   83e103               | and                 ecx, 3

        $sequence_2 = { 88442420 b97f000000 33c0 8d7c2421 }
            // n = 4, score = 100
            //   88442420             | mov                 byte ptr [esp + 0x20], al
            //   b97f000000           | mov                 ecx, 0x7f
            //   33c0                 | xor                 eax, eax
            //   8d7c2421             | lea                 edi, [esp + 0x21]

        $sequence_3 = { f3a5 8bcb 8d84244c0d0000 83e103 50 }
            // n = 5, score = 100
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   8bcb                 | mov                 ecx, ebx
            //   8d84244c0d0000       | lea                 eax, [esp + 0xd4c]
            //   83e103               | and                 ecx, 3
            //   50                   | push                eax

        $sequence_4 = { 8bcb 8d84242c040000 83e103 50 f3a4 ff15???????? }
            // n = 6, score = 100
            //   8bcb                 | mov                 ecx, ebx
            //   8d84242c040000       | lea                 eax, [esp + 0x42c]
            //   83e103               | and                 ecx, 3
            //   50                   | push                eax
            //   f3a4                 | rep movsb           byte ptr es:[edi], byte ptr [esi]
            //   ff15????????         |                     

        $sequence_5 = { c74424100a000000 8bc1 8bf7 8bfa 8d942434070000 }
            // n = 5, score = 100
            //   c74424100a000000     | mov                 dword ptr [esp + 0x10], 0xa
            //   8bc1                 | mov                 eax, ecx
            //   8bf7                 | mov                 esi, edi
            //   8bfa                 | mov                 edi, edx
            //   8d942434070000       | lea                 edx, [esp + 0x734]

        $sequence_6 = { e8???????? 83c410 85c0 0f8452010000 a1???????? }
            // n = 5, score = 100
            //   e8????????           |                     
            //   83c410               | add                 esp, 0x10
            //   85c0                 | test                eax, eax
            //   0f8452010000         | je                  0x158
            //   a1????????           |                     

        $sequence_7 = { 8bcb 4f c1e902 f3a5 8bcb 8d94243c090000 83e103 }
            // n = 7, score = 100
            //   8bcb                 | mov                 ecx, ebx
            //   4f                   | dec                 edi
            //   c1e902               | shr                 ecx, 2
            //   f3a5                 | rep movsd           dword ptr es:[edi], dword ptr [esi]
            //   8bcb                 | mov                 ecx, ebx
            //   8d94243c090000       | lea                 edx, [esp + 0x93c]
            //   83e103               | and                 ecx, 3

        $sequence_8 = { 6800058084 6a00 6a00 68???????? 52 68???????? 57 }
            // n = 7, score = 100
            //   6800058084           | push                0x84800500
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   68????????           |                     
            //   52                   | push                edx
            //   68????????           |                     
            //   57                   | push                edi

        $sequence_9 = { 83d8ff 85c0 740e 55 }
            // n = 4, score = 100
            //   83d8ff               | sbb                 eax, -1
            //   85c0                 | test                eax, eax
            //   740e                 | je                  0x10
            //   55                   | push                ebp

    condition:
        7 of them and filesize < 40960
}