rule win_lowkey_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-01-25"
        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 = "20230124"
        malpedia_hash = "2ee0eebba83dce3d019a90519f2f972c0fcf9686"
        malpedia_version = "20230125"
        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 = { 448b6c2444 b001 84c0 0f84b8000000 452be5 488d15cd64feff 4489642440 }
            // n = 7, score = 100
            //   448b6c2444           | dec                 eax
            //   b001                 | mov                 dword ptr [esp + 0x40], esi
            //   84c0                 | inc                 ebp
            //   0f84b8000000         | xor                 eax, eax
            //   452be5               | dec                 eax
            //   488d15cd64feff       | mov                 dword ptr [esp + 0x38], esi
            //   4489642440           | mov                 edx, 0x1fffff

        $sequence_1 = { 4585c0 741b 4181f800200000 7f52 }
            // n = 4, score = 100
            //   4585c0               | mov                 dword ptr [ebx - 8], eax
            //   741b                 | dec                 eax
            //   4181f800200000       | test                edi, edi
            //   7f52                 | inc                 ecx

        $sequence_2 = { 4885db 7504 33ff eb03 488b3b 8b5710 }
            // n = 6, score = 100
            //   4885db               | lea                 edx, [edi + 1]
            //   7504                 | mov                 ecx, 0x1fffff
            //   33ff                 | dec                 eax
            //   eb03                 | mov                 ebx, eax
            //   488b3b               | dec                 eax
            //   8b5710               | test                eax, eax

        $sequence_3 = { 7418 483bd8 7513 488d7b10 48897c2420 488b1f 48895c2428 }
            // n = 7, score = 100
            //   7418                 | inc                 ecx
            //   483bd8               | movzx               esi, byte ptr [ebx + eax*4 + 0x1ed93]
            //   7513                 | mov                 ebx, ecx
            //   488d7b10             | mov                 edi, eax
            //   48897c2420           | dec                 eax
            //   488b1f               | shl                 ebx, 2
            //   48895c2428           | dec                 esp

        $sequence_4 = { 488b5610 412bef 3bc5 0f4dc5 4c63c0 89461c }
            // n = 6, score = 100
            //   488b5610             | mov                 word ptr [esp + 0x55], ax
            //   412bef               | test                eax, eax
            //   3bc5                 | jne                 0x2d4
            //   0f4dc5               | dec                 eax
            //   4c63c0               | mov                 ecx, dword ptr [esp + 0x78]
            //   89461c               | dec                 eax

        $sequence_5 = { 488bd0 48035610 442bf8 443bfd 7e1c 4c8bc5 e8???????? }
            // n = 7, score = 100
            //   488bd0               | dec                 ecx
            //   48035610             | mov                 ecx, edi
            //   442bf8               | dec                 eax
            //   443bfd               | add                 edx, edi
            //   7e1c                 | inc                 ecx
            //   4c8bc5               | call                dword ptr [esp + 0x40]
            //   e8????????           |                     

        $sequence_6 = { 4883c002 4903c5 488bd0 4889442468 ff5538 488b4c2470 488906 }
            // n = 7, score = 100
            //   4883c002             | dec                 eax
            //   4903c5               | cmp                 dword ptr [ebx + 0x10], 0
            //   488bd0               | jmp                 0x9c
            //   4889442468           | je                  0xa8
            //   ff5538               | nop                 dword ptr [eax]
            //   488b4c2470           | dec                 eax
            //   488906               | mov                 ecx, eax

        $sequence_7 = { 85c9 7e1b 498d48ff 498bd6 4803c8 482bd0 8a040a }
            // n = 7, score = 100
            //   85c9                 | dec                 eax
            //   7e1b                 | mov                 ecx, edi
            //   498d48ff             | test                eax, eax
            //   498bd6               | je                  0x59
            //   4803c8               | inc                 esp
            //   482bd0               | lea                 eax, [ebx + 0x10]
            //   8a040a               | jmp                 0x35

        $sequence_8 = { 4c8bc6 488bd3 e8???????? 488b8c24b0010000 4833cc e8???????? 4881c4c0010000 }
            // n = 7, score = 100
            //   4c8bc6               | call                dword ptr [eax + 0x20]
            //   488bd3               | dec                 eax
            //   e8????????           |                     
            //   488b8c24b0010000     | mov                 ecx, dword ptr [esp + 0x50]
            //   4833cc               | dec                 esp
            //   e8????????           |                     
            //   4881c4c0010000       | lea                 ecx, [ebp - 0x30]

        $sequence_9 = { 6666660f1f840000000000 33db 488b0d???????? 488d542420 41b810000000 4863c3 442bc3 }
            // n = 7, score = 100
            //   6666660f1f840000000000     | lea    ecx, [esp + 0x20]
            //   33db                 | dec                 esp
            //   488b0d????????       |                     
            //   488d542420           | lea                 eax, [esp + 0x40]
            //   41b810000000         | mov                 dword ptr [esp + 0x20], edi
            //   4863c3               | dec                 eax
            //   442bc3               | lea                 edx, [0x20961]

    condition:
        7 of them and filesize < 643072
}