rule win_cryptomix_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.cryptomix."
        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.cryptomix"
        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 = { 8b048d48134000 ffe0 f7c703000000 7515 c1e902 83e203 }
            // n = 6, score = 200
            //   8b048d48134000       | mov                 eax, dword ptr [ecx*4 + 0x401348]
            //   ffe0                 | jmp                 eax
            //   f7c703000000         | test                edi, 3
            //   7515                 | jne                 0x17
            //   c1e902               | shr                 ecx, 2
            //   83e203               | and                 edx, 3

        $sequence_1 = { ff15???????? 68???????? 68???????? ffd7 8b8d8cefffff 8d5102 668b01 }
            // n = 7, score = 200
            //   ff15????????         |                     
            //   68????????           |                     
            //   68????????           |                     
            //   ffd7                 | call                edi
            //   8b8d8cefffff         | mov                 ecx, dword ptr [ebp - 0x1074]
            //   8d5102               | lea                 edx, [ecx + 2]
            //   668b01               | mov                 ax, word ptr [ecx]

        $sequence_2 = { e8???????? 83c414 85c0 0f8773010000 }
            // n = 4, score = 200
            //   e8????????           |                     
            //   83c414               | add                 esp, 0x14
            //   85c0                 | test                eax, eax
            //   0f8773010000         | ja                  0x179

        $sequence_3 = { 7504 6a04 eb4f 83f801 7504 }
            // n = 5, score = 200
            //   7504                 | jne                 6
            //   6a04                 | push                4
            //   eb4f                 | jmp                 0x51
            //   83f801               | cmp                 eax, 1
            //   7504                 | jne                 6

        $sequence_4 = { 8d56ec 8d4801 e8???????? 83c404 47 83c620 3b7df8 }
            // n = 7, score = 200
            //   8d56ec               | lea                 edx, [esi - 0x14]
            //   8d4801               | lea                 ecx, [eax + 1]
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   47                   | inc                 edi
            //   83c620               | add                 esi, 0x20
            //   3b7df8               | cmp                 edi, dword ptr [ebp - 8]

        $sequence_5 = { ffb588efffff 50 ff15???????? 8d85c4f9ffff 50 8d8590f5ffff }
            // n = 6, score = 200
            //   ffb588efffff         | push                dword ptr [ebp - 0x1078]
            //   50                   | push                eax
            //   ff15????????         |                     
            //   8d85c4f9ffff         | lea                 eax, [ebp - 0x63c]
            //   50                   | push                eax
            //   8d8590f5ffff         | lea                 eax, [ebp - 0xa70]

        $sequence_6 = { 7fea 8bc1 2bc2 3bc1 }
            // n = 4, score = 200
            //   7fea                 | jg                  0xffffffec
            //   8bc1                 | mov                 eax, ecx
            //   2bc2                 | sub                 eax, edx
            //   3bc1                 | cmp                 eax, ecx

        $sequence_7 = { ff742404 ffd0 c3 55 8bec 68c00f403e }
            // n = 6, score = 200
            //   ff742404             | push                dword ptr [esp + 4]
            //   ffd0                 | call                eax
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   68c00f403e           | push                0x3e400fc0

        $sequence_8 = { 50 ffd3 ff750c 8b9584efffff ffb588efffff 8d8de8fbffff }
            // n = 6, score = 200
            //   50                   | push                eax
            //   ffd3                 | call                ebx
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   8b9584efffff         | mov                 edx, dword ptr [ebp - 0x107c]
            //   ffb588efffff         | push                dword ptr [ebp - 0x1078]
            //   8d8de8fbffff         | lea                 ecx, [ebp - 0x418]

        $sequence_9 = { ff75f8 eb54 ff75fc e8???????? ff75fc e8???????? }
            // n = 6, score = 200
            //   ff75f8               | push                dword ptr [ebp - 8]
            //   eb54                 | jmp                 0x56
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   e8????????           |                     
            //   ff75fc               | push                dword ptr [ebp - 4]
            //   e8????????           |                     

        $sequence_10 = { 68c8390324 6a01 e8???????? 59 59 ff742404 ffd0 }
            // n = 7, score = 200
            //   68c8390324           | push                0x240339c8
            //   6a01                 | push                1
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   59                   | pop                 ecx
            //   ff742404             | push                dword ptr [esp + 4]
            //   ffd0                 | call                eax

        $sequence_11 = { 57 68d73d5908 6a06 e8???????? 59 }
            // n = 5, score = 200
            //   57                   | push                edi
            //   68d73d5908           | push                0x8593dd7
            //   6a06                 | push                6
            //   e8????????           |                     
            //   59                   | pop                 ecx

        $sequence_12 = { ffd0 5f 5e ff75fc }
            // n = 4, score = 200
            //   ffd0                 | call                eax
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   ff75fc               | push                dword ptr [ebp - 4]

        $sequence_13 = { e8???????? 83c408 8d8598f9ffff 50 56 ff15???????? }
            // n = 6, score = 200
            //   e8????????           |                     
            //   83c408               | add                 esp, 8
            //   8d8598f9ffff         | lea                 eax, [ebp - 0x668]
            //   50                   | push                eax
            //   56                   | push                esi
            //   ff15????????         |                     

        $sequence_14 = { 744e ffb58cefffff 8d85e8fbffff 50 ff15???????? }
            // n = 5, score = 200
            //   744e                 | je                  0x50
            //   ffb58cefffff         | push                dword ptr [ebp - 0x1074]
            //   8d85e8fbffff         | lea                 eax, [ebp - 0x418]
            //   50                   | push                eax
            //   ff15????????         |                     

        $sequence_15 = { a3???????? 8d8590efffff 50 68???????? 6a00 6a00 }
            // n = 6, score = 200
            //   a3????????           |                     
            //   8d8590efffff         | lea                 eax, [ebp - 0x1070]
            //   50                   | push                eax
            //   68????????           |                     
            //   6a00                 | push                0
            //   6a00                 | push                0

    condition:
        7 of them and filesize < 188416
}