rule win_shimrat_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.shimrat."
        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.shimrat"
        malpedia_rule_date = "20260422"
        malpedia_hash = "a182e35da64e6d71cb55f125c4d4225196523f14"
        malpedia_version = "20260504"
        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 = { 50 8d4f30 e8???????? 85c0 0f8559ffffff 33f6 46 }
            // n = 7, score = 100
            //   50                   | push                eax
            //   8d4f30               | lea                 ecx, [edi + 0x30]
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   0f8559ffffff         | jne                 0xffffff5f
            //   33f6                 | xor                 esi, esi
            //   46                   | inc                 esi

        $sequence_1 = { 83c40c 8d4d30 e8???????? 85c0 750f 81c784000000 57 }
            // n = 7, score = 100
            //   83c40c               | add                 esp, 0xc
            //   8d4d30               | lea                 ecx, [ebp + 0x30]
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   750f                 | jne                 0x11
            //   81c784000000         | add                 edi, 0x84
            //   57                   | push                edi

        $sequence_2 = { e8???????? 50 8bce e8???????? 85c0 74d9 }
            // n = 6, score = 100
            //   e8????????           |                     
            //   50                   | push                eax
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   74d9                 | je                  0xffffffdb

        $sequence_3 = { 53 3b4610 0f843cfdffff ff757c ff15???????? ff757c 8b35???????? }
            // n = 7, score = 100
            //   53                   | push                ebx
            //   3b4610               | cmp                 eax, dword ptr [esi + 0x10]
            //   0f843cfdffff         | je                  0xfffffd42
            //   ff757c               | push                dword ptr [ebp + 0x7c]
            //   ff15????????         |                     
            //   ff757c               | push                dword ptr [ebp + 0x7c]
            //   8b35????????         |                     

        $sequence_4 = { 8d45f4 50 6a1f ff75fc c745f400330000 }
            // n = 5, score = 100
            //   8d45f4               | lea                 eax, [ebp - 0xc]
            //   50                   | push                eax
            //   6a1f                 | push                0x1f
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   c745f400330000       | mov                 dword ptr [ebp - 0xc], 0x3300

        $sequence_5 = { 8bf1 57 8d4dec e8???????? 33db 895e1c ff15???????? }
            // n = 7, score = 100
            //   8bf1                 | mov                 esi, ecx
            //   57                   | push                edi
            //   8d4dec               | lea                 ecx, [ebp - 0x14]
            //   e8????????           |                     
            //   33db                 | xor                 ebx, ebx
            //   895e1c               | mov                 dword ptr [esi + 0x1c], ebx
            //   ff15????????         |                     

        $sequence_6 = { 6a01 57 8d4520 50 }
            // n = 4, score = 100
            //   6a01                 | push                1
            //   57                   | push                edi
            //   8d4520               | lea                 eax, [ebp + 0x20]
            //   50                   | push                eax

        $sequence_7 = { 59 ff75f8 ff15???????? 8bce e8???????? }
            // n = 5, score = 100
            //   59                   | pop                 ecx
            //   ff75f8               | push                dword ptr [ebp - 8]
            //   ff15????????         |                     
            //   8bce                 | mov                 ecx, esi
            //   e8????????           |                     

        $sequence_8 = { 8d4dbc e8???????? be00040000 56 8d85bcefffff 50 8d4d18 }
            // n = 7, score = 100
            //   8d4dbc               | lea                 ecx, [ebp - 0x44]
            //   e8????????           |                     
            //   be00040000           | mov                 esi, 0x400
            //   56                   | push                esi
            //   8d85bcefffff         | lea                 eax, [ebp - 0x1044]
            //   50                   | push                eax
            //   8d4d18               | lea                 ecx, [ebp + 0x18]

        $sequence_9 = { e8???????? 50 8bcb e8???????? 85c0 7409 }
            // n = 6, score = 100
            //   e8????????           |                     
            //   50                   | push                eax
            //   8bcb                 | mov                 ecx, ebx
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   7409                 | je                  0xb

    condition:
        7 of them and filesize < 65536
}