rule win_bbsrat_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.bbsrat."
        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.bbsrat"
        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 = { 56 6863001100 53 c7460800000000 c7460c00000000 e8???????? b801000000 }
            // n = 7, score = 100
            //   56                   | push                esi
            //   6863001100           | push                0x110063
            //   53                   | push                ebx
            //   c7460800000000       | mov                 dword ptr [esi + 8], 0
            //   c7460c00000000       | mov                 dword ptr [esi + 0xc], 0
            //   e8????????           |                     
            //   b801000000           | mov                 eax, 1

        $sequence_1 = { 8bd8 8b442410 6a10 89470c 55 83c010 56 }
            // n = 7, score = 100
            //   8bd8                 | mov                 ebx, eax
            //   8b442410             | mov                 eax, dword ptr [esp + 0x10]
            //   6a10                 | push                0x10
            //   89470c               | mov                 dword ptr [edi + 0xc], eax
            //   55                   | push                ebp
            //   83c010               | add                 eax, 0x10
            //   56                   | push                esi

        $sequence_2 = { 83c41c c20800 8d442408 50 e8???????? 33c9 83c404 }
            // n = 7, score = 100
            //   83c41c               | add                 esp, 0x1c
            //   c20800               | ret                 8
            //   8d442408             | lea                 eax, [esp + 8]
            //   50                   | push                eax
            //   e8????????           |                     
            //   33c9                 | xor                 ecx, ecx
            //   83c404               | add                 esp, 4

        $sequence_3 = { 6a00 6800000040 52 ffd5 8bf0 83feff 750a }
            // n = 7, score = 100
            //   6a00                 | push                0
            //   6800000040           | push                0x40000000
            //   52                   | push                edx
            //   ffd5                 | call                ebp
            //   8bf0                 | mov                 esi, eax
            //   83feff               | cmp                 esi, -1
            //   750a                 | jne                 0xc

        $sequence_4 = { 83fefb 751f 8b4b28 57 51 c74318bcc30210 befdffffff }
            // n = 7, score = 100
            //   83fefb               | cmp                 esi, -5
            //   751f                 | jne                 0x21
            //   8b4b28               | mov                 ecx, dword ptr [ebx + 0x28]
            //   57                   | push                edi
            //   51                   | push                ecx
            //   c74318bcc30210       | mov                 dword ptr [ebx + 0x18], 0x1002c3bc
            //   befdffffff           | mov                 esi, 0xfffffffd

        $sequence_5 = { 2bc2 8b542428 50 68???????? 52 ff15???????? }
            // n = 6, score = 100
            //   2bc2                 | sub                 eax, edx
            //   8b542428             | mov                 edx, dword ptr [esp + 0x28]
            //   50                   | push                eax
            //   68????????           |                     
            //   52                   | push                edx
            //   ff15????????         |                     

        $sequence_6 = { 56 50 e8???????? 8b4b14 33c0 89442460 }
            // n = 6, score = 100
            //   56                   | push                esi
            //   50                   | push                eax
            //   e8????????           |                     
            //   8b4b14               | mov                 ecx, dword ptr [ebx + 0x14]
            //   33c0                 | xor                 eax, eax
            //   89442460             | mov                 dword ptr [esp + 0x60], eax

        $sequence_7 = { 8d47ff c644241c01 83f81f 7713 0fb69018a20010 ff249510a20010 }
            // n = 6, score = 100
            //   8d47ff               | lea                 eax, [edi - 1]
            //   c644241c01           | mov                 byte ptr [esp + 0x1c], 1
            //   83f81f               | cmp                 eax, 0x1f
            //   7713                 | ja                  0x15
            //   0fb69018a20010       | movzx               edx, byte ptr [eax + 0x1000a218]
            //   ff249510a20010       | jmp                 dword ptr [edx*4 + 0x1000a210]

        $sequence_8 = { 8bc6 895c2438 8bd1 894c247c 83fe04 7227 8da42400000000 }
            // n = 7, score = 100
            //   8bc6                 | mov                 eax, esi
            //   895c2438             | mov                 dword ptr [esp + 0x38], ebx
            //   8bd1                 | mov                 edx, ecx
            //   894c247c             | mov                 dword ptr [esp + 0x7c], ecx
            //   83fe04               | cmp                 esi, 4
            //   7227                 | jb                  0x29
            //   8da42400000000       | lea                 esp, [esp]

        $sequence_9 = { 03c0 50 8b44240c 8d542418 }
            // n = 4, score = 100
            //   03c0                 | add                 eax, eax
            //   50                   | push                eax
            //   8b44240c             | mov                 eax, dword ptr [esp + 0xc]
            //   8d542418             | lea                 edx, [esp + 0x18]

    condition:
        7 of them and filesize < 434176
}