rule win_bunitu_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.bunitu."
        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.bunitu"
        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 = { 8bf7 03d8 ebdf 8bb544feffff }
            // n = 4, score = 1300
            //   8bf7                 | mov                 esi, edi
            //   03d8                 | add                 ebx, eax
            //   ebdf                 | jmp                 0xffffffe1
            //   8bb544feffff         | mov                 esi, dword ptr [ebp - 0x1bc]

        $sequence_1 = { 57 8d859cf7ffff 50 e8???????? 8d8d9cf7ffff 51 }
            // n = 6, score = 1300
            //   57                   | push                edi
            //   8d859cf7ffff         | lea                 eax, [ebp - 0x864]
            //   50                   | push                eax
            //   e8????????           |                     
            //   8d8d9cf7ffff         | lea                 ecx, [ebp - 0x864]
            //   51                   | push                ecx

        $sequence_2 = { ffb544feffff 51 6800040000 6a00 ff15???????? }
            // n = 5, score = 1300
            //   ffb544feffff         | push                dword ptr [ebp - 0x1bc]
            //   51                   | push                ecx
            //   6800040000           | push                0x400
            //   6a00                 | push                0
            //   ff15????????         |                     

        $sequence_3 = { 60 8b7d08 8b9774130000 8955e0 8b9778130000 8955dc }
            // n = 6, score = 1300
            //   60                   | pushal              
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]
            //   8b9774130000         | mov                 edx, dword ptr [edi + 0x1374]
            //   8955e0               | mov                 dword ptr [ebp - 0x20], edx
            //   8b9778130000         | mov                 edx, dword ptr [edi + 0x1378]
            //   8955dc               | mov                 dword ptr [ebp - 0x24], edx

        $sequence_4 = { b970170000 f2ae 2bfa 87fa 5f 8bc2 }
            // n = 6, score = 1300
            //   b970170000           | mov                 ecx, 0x1770
            //   f2ae                 | repne scasb         al, byte ptr es:[edi]
            //   2bfa                 | sub                 edi, edx
            //   87fa                 | xchg                edx, edi
            //   5f                   | pop                 edi
            //   8bc2                 | mov                 eax, edx

        $sequence_5 = { 81c498f7ffff 57 8dbd9cf7ffff 2bc0 b968080000 f3aa 5f }
            // n = 7, score = 1300
            //   81c498f7ffff         | add                 esp, 0xfffff798
            //   57                   | push                edi
            //   8dbd9cf7ffff         | lea                 edi, [ebp - 0x864]
            //   2bc0                 | sub                 eax, eax
            //   b968080000           | mov                 ecx, 0x868
            //   f3aa                 | rep stosb           byte ptr es:[edi], al
            //   5f                   | pop                 edi

        $sequence_6 = { 87fa 5f 8bc2 48 40 8d443825 668b00 }
            // n = 7, score = 1300
            //   87fa                 | xchg                edx, edi
            //   5f                   | pop                 edi
            //   8bc2                 | mov                 eax, edx
            //   48                   | dec                 eax
            //   40                   | inc                 eax
            //   8d443825             | lea                 eax, [eax + edi + 0x25]
            //   668b00               | mov                 ax, word ptr [eax]

        $sequence_7 = { 50 8f06 33db 83c301 d1e3 d1e3 03fb }
            // n = 7, score = 1300
            //   50                   | push                eax
            //   8f06                 | pop                 dword ptr [esi]
            //   33db                 | xor                 ebx, ebx
            //   83c301               | add                 ebx, 1
            //   d1e3                 | shl                 ebx, 1
            //   d1e3                 | shl                 ebx, 1
            //   03fb                 | add                 edi, ebx

        $sequence_8 = { 6800100000 50 ff75fc e8???????? }
            // n = 4, score = 1300
            //   6800100000           | push                0x1000
            //   50                   | push                eax
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   e8????????           |                     

        $sequence_9 = { 59 8bd0 8bdf b82f000000 }
            // n = 4, score = 1300
            //   59                   | pop                 ecx
            //   8bd0                 | mov                 edx, eax
            //   8bdf                 | mov                 ebx, edi
            //   b82f000000           | mov                 eax, 0x2f

    condition:
        7 of them and filesize < 221184
}