rule win_lowkey_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-11-21"
        version = "1"
        description = "Detects win.lowkey."
        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.lowkey"
        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 = { e8???????? 85c0 751a 488d0d8b7f0400 ff15???????? 33c0 488b742438 }
            // n = 7, score = 100
            //   e8????????           |                     
            //   85c0                 | mov                 word ptr [esp + 0x148], ax
            //   751a                 | mov                 ebp, 2
            //   488d0d8b7f0400       | dec                 eax
            //   ff15????????         |                     
            //   33c0                 | lea                 eax, [0x239ed]
            //   488b742438           | dec                 eax

        $sequence_1 = { 8b7e20 3bc7 756d 448b7e18 488bd0 48035610 442bf8 }
            // n = 7, score = 100
            //   8b7e20               | mov                 ebx, edi
            //   3bc7                 | dec                 eax
            //   756d                 | mov                 dword ptr [esp + 0x38], ebx
            //   448b7e18             | dec                 eax
            //   488bd0               | test                ebx, ebx
            //   48035610             | je                  0x7db
            //   442bf8               | dec                 eax

        $sequence_2 = { 4889442458 488bc2 488bf1 33db bd01000000 48895c2430 4533c9 }
            // n = 7, score = 100
            //   4889442458           | je                  0xa60
            //   488bc2               | inc                 ecx
            //   488bf1               | mov                 ecx, dword ptr [edi + 0x18]
            //   33db                 | inc                 ecx
            //   bd01000000           | mov                 eax, 0x1000
            //   48895c2430           | call                dword ptr [ebp + 0x30]
            //   4533c9               | test                eax, eax

        $sequence_3 = { 4c8bce 0f104b10 498bd6 48890e 0f2945a0 0f104320 4c897930 }
            // n = 7, score = 100
            //   4c8bce               | dec                 esp
            //   0f104b10             | lea                 esi, [esi + 8]
            //   498bd6               | dec                 ecx
            //   48890e               | mov                 ecx, esi
            //   0f2945a0             | xor                 ebx, ebx
            //   0f104320             | dec                 eax
            //   4c897930             | mov                 dword ptr [esp + 0x30], edi

        $sequence_4 = { 4157 4883ec20 488b02 4533ff 4c8bf1 }
            // n = 5, score = 100
            //   4157                 | jl                  0x109
            //   4883ec20             | inc                 ebp
            //   488b02               | mov                 eax, ecx
            //   4533ff               | dec                 esp
            //   4c8bf1               | mov                 edx, ecx

        $sequence_5 = { 418a03 413a841968f00100 740a 413a84196cf00100 7542 48ff4210 488b4210 }
            // n = 7, score = 100
            //   418a03               | mov                 eax, 0x10
            //   413a841968f00100     | nop                 
            //   740a                 | xor                 eax, eax
            //   413a84196cf00100     | dec                 eax
            //   7542                 | mov                 dword ptr [esp + 0x38], edi
            //   48ff4210             | dec                 eax
            //   488b4210             | lea                 eax, [esp + 0x70]

        $sequence_6 = { 48898580290000 4c8bf2 488d8d70010000 33d2 41b800020000 e8???????? }
            // n = 6, score = 100
            //   48898580290000       | inc                 ecx
            //   4c8bf2               | pop                 esp
            //   488d8d70010000       | pop                 edi
            //   33d2                 | pop                 esi
            //   41b800020000         | pop                 ebp
            //   e8????????           |                     

        $sequence_7 = { ff15???????? 885c2473 807c24713a 746b 33d2 488d8d70030000 41b8f4010000 }
            // n = 7, score = 100
            //   ff15????????         |                     
            //   885c2473             | test                eax, eax
            //   807c24713a           | je                  0xe53
            //   746b                 | jmp                 0xa78
            //   33d2                 | dec                 esp
            //   488d8d70030000       | lea                 ebx, [0xffff0226]
            //   41b8f4010000         | inc                 esp

        $sequence_8 = { 7565 33c0 4c8bb42488210000 4c8ba424c0210000 488bb424b0210000 4c8bbc2480210000 488b8d70200000 }
            // n = 7, score = 100
            //   7565                 | dec                 eax
            //   33c0                 | lea                 ecx, [0x18ebd]
            //   4c8bb42488210000     | dec                 eax
            //   4c8ba424c0210000     | lea                 eax, [esp + 0x68]
            //   488bb424b0210000     | dec                 eax
            //   4c8bbc2480210000     | mov                 dword ptr [esp + 0x48], eax
            //   488b8d70200000       | dec                 eax

        $sequence_9 = { 41890f 4885d8 752c 4985dc 7527 488b9540070000 4c8d0597a80000 }
            // n = 7, score = 100
            //   41890f               | lea                 eax, [esp + 0x30]
            //   4885d8               | mov                 dword ptr [esp + 0x34], esi
            //   752c                 | inc                 ebp
            //   4985dc               | xor                 ecx, ecx
            //   7527                 | lea                 ebp, [edi + 1]
            //   488b9540070000       | test                esi, esi
            //   4c8d0597a80000       | jle                 0x14b

    condition:
        7 of them and filesize < 643072
}