rule win_cryptic_convo_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-05-04"
        version = "1"
        description = "Detects win.cryptic_convo."
        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.cryptic_convo"
        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 = { b8???????? a4 8bf0 8a08 40 84c9 75f9 }
            // n = 7, score = 100
            //   b8????????           |                     
            //   a4                   | movsb               byte ptr es:[edi], byte ptr [esi]
            //   8bf0                 | mov                 esi, eax
            //   8a08                 | mov                 cl, byte ptr [eax]
            //   40                   | inc                 eax
            //   84c9                 | test                cl, cl
            //   75f9                 | jne                 0xfffffffb

        $sequence_1 = { 8945e0 8d4584 6a00 50 }
            // n = 4, score = 100
            //   8945e0               | mov                 dword ptr [ebp - 0x20], eax
            //   8d4584               | lea                 eax, [ebp - 0x7c]
            //   6a00                 | push                0
            //   50                   | push                eax

        $sequence_2 = { 59 7e2d 8b4d8c 8b5584 49 4a }
            // n = 6, score = 100
            //   59                   | pop                 ecx
            //   7e2d                 | jle                 0x2f
            //   8b4d8c               | mov                 ecx, dword ptr [ebp - 0x74]
            //   8b5584               | mov                 edx, dword ptr [ebp - 0x7c]
            //   49                   | dec                 ecx
            //   4a                   | dec                 edx

        $sequence_3 = { 8b45a0 2b4598 2bc3 40 99 2bc2 }
            // n = 6, score = 100
            //   8b45a0               | mov                 eax, dword ptr [ebp - 0x60]
            //   2b4598               | sub                 eax, dword ptr [ebp - 0x68]
            //   2bc3                 | sub                 eax, ebx
            //   40                   | inc                 eax
            //   99                   | cdq                 
            //   2bc2                 | sub                 eax, edx

        $sequence_4 = { 50 e8???????? 83c410 53 ff15???????? 59 8b4dfc }
            // n = 7, score = 100
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c410               | add                 esp, 0x10
            //   53                   | push                ebx
            //   ff15????????         |                     
            //   59                   | pop                 ecx
            //   8b4dfc               | mov                 ecx, dword ptr [ebp - 4]

        $sequence_5 = { ff15???????? 53 57 894588 ff15???????? }
            // n = 5, score = 100
            //   ff15????????         |                     
            //   53                   | push                ebx
            //   57                   | push                edi
            //   894588               | mov                 dword ptr [ebp - 0x78], eax
            //   ff15????????         |                     

        $sequence_6 = { be???????? 8d7dc8 a5 a4 8d7dc8 }
            // n = 5, score = 100
            //   be????????           |                     
            //   8d7dc8               | lea                 edi, [ebp - 0x38]
            //   a5                   | movsd               dword ptr es:[edi], dword ptr [esi]
            //   a4                   | movsb               byte ptr es:[edi], byte ptr [esi]
            //   8d7dc8               | lea                 edi, [ebp - 0x38]

        $sequence_7 = { 397510 7e36 ff15???????? 6a19 59 99 f7f9 }
            // n = 7, score = 100
            //   397510               | cmp                 dword ptr [ebp + 0x10], esi
            //   7e36                 | jle                 0x38
            //   ff15????????         |                     
            //   6a19                 | push                0x19
            //   59                   | pop                 ecx
            //   99                   | cdq                 
            //   f7f9                 | idiv                ecx

        $sequence_8 = { be???????? 8d7dc8 a5 a4 8d7dc8 83c40c }
            // n = 6, score = 100
            //   be????????           |                     
            //   8d7dc8               | lea                 edi, [ebp - 0x38]
            //   a5                   | movsd               dword ptr es:[edi], dword ptr [esi]
            //   a4                   | movsb               byte ptr es:[edi], byte ptr [esi]
            //   8d7dc8               | lea                 edi, [ebp - 0x38]
            //   83c40c               | add                 esp, 0xc

        $sequence_9 = { 83c008 50 ff33 ff15???????? 8b37 }
            // n = 5, score = 100
            //   83c008               | add                 eax, 8
            //   50                   | push                eax
            //   ff33                 | push                dword ptr [ebx]
            //   ff15????????         |                     
            //   8b37                 | mov                 esi, dword ptr [edi]

    condition:
        7 of them and filesize < 97280
}