rule win_skynet_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        version = "1"
        description = "Detects win.skynet."
        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.skynet"
        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 = { 488d1517ba8c00 4889f1 e8???????? 85c0 74de 488d7b10 }
            // n = 6, score = 100
            //   488d1517ba8c00       | mov                 dword ptr [eax + 0x18], 0
            //   4889f1               | dec                 eax
            //   e8????????           |                     
            //   85c0                 | lea                 eax, [0x8ec2f4]
            //   74de                 | dec                 eax
            //   488d7b10             | mov                 dword ptr [ecx], eax

        $sequence_1 = { 488903 0f16442450 0f114308 4885c9 0f845f010000 48894c2440 }
            // n = 6, score = 100
            //   488903               | lea                 ebp, [0x8d6407]
            //   0f16442450           | dec                 eax
            //   0f114308             | lea                 esi, [ecx + 0xd0]
            //   4885c9               | dec                 eax
            //   0f845f010000         | mov                 ebx, ecx
            //   48894c2440           | dec                 eax

        $sequence_2 = { 4989c1 4883ff01 0f84a1010000 4c89d2 4c89c9 4989f8 }
            // n = 6, score = 100
            //   4989c1               | mov                 dword ptr [ecx + 8], eax
            //   4883ff01             | dec                 eax
            //   0f84a1010000         | lea                 eax, [0x8d637e]
            //   4c89d2               | dec                 eax
            //   4c89c9               | mov                 dword ptr [ecx], eax
            //   4989f8               | mov                 byte ptr [ecx + 0x20], 0

        $sequence_3 = { 668983f8000000 0fb687e2000000 8883fa000000 488d054dc28d00 48c7460800000000 488d7028 }
            // n = 6, score = 100
            //   668983f8000000       | dec                 eax
            //   0fb687e2000000       | mov                 ecx, ebp
            //   8883fa000000         | pop                 ebp
            //   488d054dc28d00       | inc                 ecx
            //   48c7460800000000     | pop                 esp
            //   488d7028             | ret                 

        $sequence_4 = { 488b8424f0000000 488dbc2400010000 488b8c2490000000 48897c2430 4c8b8424f8000000 }
            // n = 5, score = 100
            //   488b8424f0000000     | je                  0x1613
            //   488dbc2400010000     | dec                 cx
            //   488b8c2490000000     | movd                mm0, eax
            //   48897c2430           | dec                 eax
            //   4c8b8424f8000000     | mov                 ecx, dword ptr [esp + 0x20]

        $sequence_5 = { 29c2 89c8 c1e008 8d8402c0fdffff 8944240c 8b44240c 3d41010000 }
            // n = 7, score = 100
            //   29c2                 | ja                  0x176
            //   89c8                 | mov                 eax, eax
            //   c1e008               | dec                 eax
            //   8d8402c0fdffff       | lea                 edx, [eax*4]
            //   8944240c             | dec                 eax
            //   8b44240c             | lea                 eax, [0x96a75d]
            //   3d41010000           | movzx               eax, byte ptr [eax]

        $sequence_6 = { 482b4508 4c39c0 0f8296000000 4889e9 e8???????? e9???????? 488bbc2418010000 }
            // n = 7, score = 100
            //   482b4508             | pop                 esi
            //   4c39c0               | pop                 edi
            //   0f8296000000         | inc                 ebp
            //   4889e9               | sub                 ecx, eax
            //   e8????????           |                     
            //   e9????????           |                     
            //   488bbc2418010000     | dec                 esp

        $sequence_7 = { 4889842470010000 488d842460010000 48898c2468010000 488b4c2448 4889c2 4889442468 e8???????? }
            // n = 7, score = 100
            //   4889842470010000     | mov                 ecx, ebx
            //   488d842460010000     | dec                 eax
            //   48898c2468010000     | mov                 dword ptr [edi], ebp
            //   488b4c2448           | dec                 eax
            //   4889c2               | test                edx, edx
            //   4889442468           | je                  0x877
            //   e8????????           |                     

        $sequence_8 = { 4881ecf8040000 4889ce 4885c9 0f84d9000000 488d3dba3c9500 4889f9 }
            // n = 6, score = 100
            //   4881ecf8040000       | jae                 0x177
            //   4889ce               | movzx               ecx, byte ptr [edi + eax + 0xf]
            //   4885c9               | xor                 cl, byte ptr [edx + 0xf]
            //   0f84d9000000         | mov                 byte ptr [esi + eax + 0xf], cl
            //   488d3dba3c9500       | dec                 eax
            //   4889f9               | mov                 eax, ebp

        $sequence_9 = { 83f808 731c a804 755f 85c0 740b 0fb65310 }
            // n = 7, score = 100
            //   83f808               | dec                 eax
            //   731c                 | mov                 dword ptr [esp + 0x30], eax
            //   a804                 | dec                 eax
            //   755f                 | mov                 eax, dword ptr [esp + 0x88]
            //   85c0                 | movups              xmmword ptr [ebx + 0x10], xmm0
            //   740b                 | dec                 esp
            //   0fb65310             | cmp                 eax, esp

    condition:
        7 of them and filesize < 20419584
}