rule win_geminiduke_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.geminiduke."
        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.geminiduke"
        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 = { 8b7c2410 8b442414 8b4c2418 f3aa 5f 59 }
            // n = 6, score = 400
            //   8b7c2410             | mov                 edi, dword ptr [esp + 0x10]
            //   8b442414             | mov                 eax, dword ptr [esp + 0x14]
            //   8b4c2418             | mov                 ecx, dword ptr [esp + 0x18]
            //   f3aa                 | rep stosb           byte ptr es:[edi], al
            //   5f                   | pop                 edi
            //   59                   | pop                 ecx

        $sequence_1 = { 6819000200 6a00 68???????? e8???????? 83c404 }
            // n = 5, score = 400
            //   6819000200           | push                0x20019
            //   6a00                 | push                0
            //   68????????           |                     
            //   e8????????           |                     
            //   83c404               | add                 esp, 4

        $sequence_2 = { 50 51 57 8b7c2410 }
            // n = 4, score = 400
            //   50                   | push                eax
            //   51                   | push                ecx
            //   57                   | push                edi
            //   8b7c2410             | mov                 edi, dword ptr [esp + 0x10]

        $sequence_3 = { 83c404 50 6801000080 ff15???????? 85c0 7407 33c0 }
            // n = 7, score = 400
            //   83c404               | add                 esp, 4
            //   50                   | push                eax
            //   6801000080           | push                0x80000001
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   7407                 | je                  9
            //   33c0                 | xor                 eax, eax

        $sequence_4 = { 034590 03c8 894dd0 8b45f8 }
            // n = 4, score = 300
            //   034590               | add                 eax, dword ptr [ebp - 0x70]
            //   03c8                 | add                 ecx, eax
            //   894dd0               | mov                 dword ptr [ebp - 0x30], ecx
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]

        $sequence_5 = { 034584 8b8d64ffffff c1e907 8b9564ffffff c1e219 0bca 8b9564ffffff }
            // n = 7, score = 300
            //   034584               | add                 eax, dword ptr [ebp - 0x7c]
            //   8b8d64ffffff         | mov                 ecx, dword ptr [ebp - 0x9c]
            //   c1e907               | shr                 ecx, 7
            //   8b9564ffffff         | mov                 edx, dword ptr [ebp - 0x9c]
            //   c1e219               | shl                 edx, 0x19
            //   0bca                 | or                  ecx, edx
            //   8b9564ffffff         | mov                 edx, dword ptr [ebp - 0x9c]

        $sequence_6 = { 034590 8b8d70ffffff c1e907 8b9570ffffff }
            // n = 4, score = 300
            //   034590               | add                 eax, dword ptr [ebp - 0x70]
            //   8b8d70ffffff         | mov                 ecx, dword ptr [ebp - 0x90]
            //   c1e907               | shr                 ecx, 7
            //   8b9570ffffff         | mov                 edx, dword ptr [ebp - 0x90]

        $sequence_7 = { 03459c 03c8 894ddc 8b45fc }
            // n = 4, score = 300
            //   03459c               | add                 eax, dword ptr [ebp - 0x64]
            //   03c8                 | add                 ecx, eax
            //   894ddc               | mov                 dword ptr [ebp - 0x24], ecx
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]

        $sequence_8 = { 57 8b7c240c 6a01 6a00 8bf1 }
            // n = 5, score = 200
            //   57                   | push                edi
            //   8b7c240c             | mov                 edi, dword ptr [esp + 0xc]
            //   6a01                 | push                1
            //   6a00                 | push                0
            //   8bf1                 | mov                 esi, ecx

        $sequence_9 = { 8ac8 80e961 80f919 7703 b001 c3 2c41 }
            // n = 7, score = 200
            //   8ac8                 | mov                 cl, al
            //   80e961               | sub                 cl, 0x61
            //   80f919               | cmp                 cl, 0x19
            //   7703                 | ja                  5
            //   b001                 | mov                 al, 1
            //   c3                   | ret                 
            //   2c41                 | sub                 al, 0x41

        $sequence_10 = { 2500800000 50 8bcf e8???????? 8be8 8bc3 2500020000 }
            // n = 7, score = 200
            //   2500800000           | and                 eax, 0x8000
            //   50                   | push                eax
            //   8bcf                 | mov                 ecx, edi
            //   e8????????           |                     
            //   8be8                 | mov                 ebp, eax
            //   8bc3                 | mov                 eax, ebx
            //   2500020000           | and                 eax, 0x200

        $sequence_11 = { 8b770c 89442410 8b4704 8bc8 }
            // n = 4, score = 200
            //   8b770c               | mov                 esi, dword ptr [edi + 0xc]
            //   89442410             | mov                 dword ptr [esp + 0x10], eax
            //   8b4704               | mov                 eax, dword ptr [edi + 4]
            //   8bc8                 | mov                 ecx, eax

        $sequence_12 = { 56 57 8bf9 8b4724 8b5f08 8b770c 89442410 }
            // n = 7, score = 200
            //   56                   | push                esi
            //   57                   | push                edi
            //   8bf9                 | mov                 edi, ecx
            //   8b4724               | mov                 eax, dword ptr [edi + 0x24]
            //   8b5f08               | mov                 ebx, dword ptr [edi + 8]
            //   8b770c               | mov                 esi, dword ptr [edi + 0xc]
            //   89442410             | mov                 dword ptr [esp + 0x10], eax

        $sequence_13 = { 7704 8ac1 0430 8ad1 80ea0a 80fa05 7705 }
            // n = 7, score = 200
            //   7704                 | ja                  6
            //   8ac1                 | mov                 al, cl
            //   0430                 | add                 al, 0x30
            //   8ad1                 | mov                 dl, cl
            //   80ea0a               | sub                 dl, 0xa
            //   80fa05               | cmp                 dl, 5
            //   7705                 | ja                  7

    condition:
        7 of them and filesize < 327680
}