rule win_ranbyus_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        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 = "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 = { 8a06 3c46 7240 3c47 }
            // n = 4, score = 1100
            //   8a06                 | mov                 al, byte ptr [esi]
            //   3c46                 | cmp                 al, 0x46
            //   7240                 | jb                  0x42
            //   3c47                 | cmp                 al, 0x47

        $sequence_1 = { 8bc8 e8???????? 50 e8???????? 8bf0 59 }
            // n = 6, score = 1100
            //   8bc8                 | mov                 ecx, eax
            //   e8????????           |                     
            //   50                   | push                eax
            //   e8????????           |                     
            //   8bf0                 | mov                 esi, eax
            //   59                   | pop                 ecx

        $sequence_2 = { 837c240400 7458 57 ff74240c }
            // n = 4, score = 1100
            //   837c240400           | cmp                 dword ptr [esp + 4], 0
            //   7458                 | je                  0x5a
            //   57                   | push                edi
            //   ff74240c             | push                dword ptr [esp + 0xc]

        $sequence_3 = { 8bc8 e8???????? 50 8bce e8???????? 894604 }
            // n = 6, score = 1100
            //   8bc8                 | mov                 ecx, eax
            //   e8????????           |                     
            //   50                   | push                eax
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     
            //   894604               | mov                 dword ptr [esi + 4], eax

        $sequence_4 = { 8bec 51 837d0c00 7513 68???????? ff7508 e8???????? }
            // n = 7, 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]
            //   e8????????           |                     

        $sequence_5 = { 8bf8 3b7e14 760b 56 e8???????? 59 }
            // n = 6, score = 1100
            //   8bf8                 | mov                 edi, eax
            //   3b7e14               | cmp                 edi, dword ptr [esi + 0x14]
            //   760b                 | jbe                 0xd
            //   56                   | push                esi
            //   e8????????           |                     
            //   59                   | pop                 ecx

        $sequence_6 = { 50 50 50 68???????? 68???????? e8???????? 83c418 }
            // n = 7, score = 1100
            //   50                   | push                eax
            //   50                   | push                eax
            //   50                   | push                eax
            //   68????????           |                     
            //   68????????           |                     
            //   e8????????           |                     
            //   83c418               | add                 esp, 0x18

        $sequence_7 = { 8b4e05 89410b 8b4605 39780b }
            // n = 4, score = 1100
            //   8b4e05               | mov                 ecx, dword ptr [esi + 5]
            //   89410b               | mov                 dword ptr [ecx + 0xb], eax
            //   8b4605               | mov                 eax, dword ptr [esi + 5]
            //   39780b               | cmp                 dword ptr [eax + 0xb], edi

        $sequence_8 = { 7524 814e2580000000 8b03 89461a eb16 834e2540 668b03 }
            // n = 7, score = 1100
            //   7524                 | jne                 0x26
            //   814e2580000000       | or                  dword ptr [esi + 0x25], 0x80
            //   8b03                 | mov                 eax, dword ptr [ebx]
            //   89461a               | mov                 dword ptr [esi + 0x1a], eax
            //   eb16                 | jmp                 0x18
            //   834e2540             | or                  dword ptr [esi + 0x25], 0x40
            //   668b03               | mov                 ax, word ptr [ebx]

        $sequence_9 = { 7504 8bf0 ebeb 6a03 }
            // n = 4, score = 1100
            //   7504                 | jne                 6
            //   8bf0                 | mov                 esi, eax
            //   ebeb                 | jmp                 0xffffffed
            //   6a03                 | push                3

    condition:
        7 of them and filesize < 638976
}