rule win_ranbyus_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-11-21"
        version = "1"
        description = "Detects win.ranbyus."
        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.ranbyus"
        malpedia_rule_date = "20221118"
        malpedia_hash = "e0702e2e6d1d00da65c8a29a4ebacd0a4c59e1af"
        malpedia_version = "20221125"
        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 = { 803c3e5c 75f5 8bc6 46 85c0 }
            // n = 5, score = 1100
            //   803c3e5c             | cmp                 byte ptr [esi + edi], 0x5c
            //   75f5                 | jne                 0xfffffff7
            //   8bc6                 | mov                 eax, esi
            //   46                   | inc                 esi
            //   85c0                 | test                eax, eax

        $sequence_1 = { 8bec 51 837d0c00 7513 68???????? ff7508 }
            // n = 6, score = 1100
            //   8bec                 | mov                 ebp, esp
            //   51                   | push                ecx
            //   837d0c00             | cmp                 dword ptr [ebp + 0xc], 0
            //   7513                 | jne                 0x15
            //   68????????           |                     
            //   ff7508               | push                dword ptr [ebp + 8]

        $sequence_2 = { 8b4c2408 2b4c2404 0fafc1 c1e80f }
            // n = 4, score = 1100
            //   8b4c2408             | mov                 ecx, dword ptr [esp + 8]
            //   2b4c2404             | sub                 ecx, dword ptr [esp + 4]
            //   0fafc1               | imul                eax, ecx
            //   c1e80f               | shr                 eax, 0xf

        $sequence_3 = { e8???????? 50 e8???????? 59 33c0 c3 55 }
            // n = 7, score = 1100
            //   e8????????           |                     
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   33c0                 | xor                 eax, eax
            //   c3                   | ret                 
            //   55                   | push                ebp

        $sequence_4 = { 6a10 e8???????? 8bf0 59 85f6 741a }
            // n = 6, score = 1100
            //   6a10                 | push                0x10
            //   e8????????           |                     
            //   8bf0                 | mov                 esi, eax
            //   59                   | pop                 ecx
            //   85f6                 | test                esi, esi
            //   741a                 | je                  0x1c

        $sequence_5 = { e8???????? 59 33c0 eb03 83c8ff }
            // n = 5, score = 1100
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   33c0                 | xor                 eax, eax
            //   eb03                 | jmp                 5
            //   83c8ff               | or                  eax, 0xffffffff

        $sequence_6 = { 85c0 7427 8b4818 85c9 740f 3b4c2404 }
            // n = 6, score = 1100
            //   85c0                 | test                eax, eax
            //   7427                 | je                  0x29
            //   8b4818               | mov                 ecx, dword ptr [eax + 0x18]
            //   85c9                 | test                ecx, ecx
            //   740f                 | je                  0x11
            //   3b4c2404             | cmp                 ecx, dword ptr [esp + 4]

        $sequence_7 = { e8???????? 59 897304 682c010000 }
            // n = 4, score = 1100
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   897304               | mov                 dword ptr [ebx + 4], esi
            //   682c010000           | push                0x12c

        $sequence_8 = { 740c 803c305c 7405 48 75f7 eb01 40 }
            // n = 7, score = 1100
            //   740c                 | je                  0xe
            //   803c305c             | cmp                 byte ptr [eax + esi], 0x5c
            //   7405                 | je                  7
            //   48                   | dec                 eax
            //   75f7                 | jne                 0xfffffff9
            //   eb01                 | jmp                 3
            //   40                   | inc                 eax

        $sequence_9 = { 8bc8 e8???????? 50 8d8500fcffff }
            // n = 4, score = 1100
            //   8bc8                 | mov                 ecx, eax
            //   e8????????           |                     
            //   50                   | push                eax
            //   8d8500fcffff         | lea                 eax, [ebp - 0x400]

    condition:
        7 of them and filesize < 638976
}