rule win_conficker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-04-08"
        version = "1"
        description = "Detects win.conficker."
        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.conficker"
        malpedia_rule_date = "20220405"
        malpedia_hash = "ecd38294bd47d5589be5cd5490dc8bb4804afc2a"
        malpedia_version = "20220411"
        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 = { 80fc05 75c5 fec8 74c1 80c204 ebbc }
            // n = 6, score = 300
            //   80fc05               | cmp                 ah, 5
            //   75c5                 | jne                 0xffffffc7
            //   fec8                 | dec                 al
            //   74c1                 | je                  0xffffffc3
            //   80c204               | add                 dl, 4
            //   ebbc                 | jmp                 0xffffffbe

        $sequence_1 = { 3345f8 33c7 33c6 50 ff15???????? 59 5f }
            // n = 7, score = 300
            //   3345f8               | xor                 eax, dword ptr [ebp - 8]
            //   33c7                 | xor                 eax, edi
            //   33c6                 | xor                 eax, esi
            //   50                   | push                eax
            //   ff15????????         |                     
            //   59                   | pop                 ecx
            //   5f                   | pop                 edi

        $sequence_2 = { 8b048e 8b1c8f 3bc3 7209 770e 49 79f1 }
            // n = 7, score = 300
            //   8b048e               | mov                 eax, dword ptr [esi + ecx*4]
            //   8b1c8f               | mov                 ebx, dword ptr [edi + ecx*4]
            //   3bc3                 | cmp                 eax, ebx
            //   7209                 | jb                  0xb
            //   770e                 | ja                  0x10
            //   49                   | dec                 ecx
            //   79f1                 | jns                 0xfffffff3

        $sequence_3 = { e8???????? 8bd0 83c410 85d2 0f8c9c000000 56 }
            // n = 6, score = 300
            //   e8????????           |                     
            //   8bd0                 | mov                 edx, eax
            //   83c410               | add                 esp, 0x10
            //   85d2                 | test                edx, edx
            //   0f8c9c000000         | jl                  0xa2
            //   56                   | push                esi

        $sequence_4 = { df6df8 8365f800 894dfc 2175fc d9e0 23cf dec1 }
            // n = 7, score = 300
            //   df6df8               | fild                qword ptr [ebp - 8]
            //   8365f800             | and                 dword ptr [ebp - 8], 0
            //   894dfc               | mov                 dword ptr [ebp - 4], ecx
            //   2175fc               | and                 dword ptr [ebp - 4], esi
            //   d9e0                 | fchs                
            //   23cf                 | and                 ecx, edi
            //   dec1                 | faddp               st(1)

        $sequence_5 = { e2f4 4a 0f8968ffffff 5f 5e 5d }
            // n = 6, score = 300
            //   e2f4                 | loop                0xfffffff6
            //   4a                   | dec                 edx
            //   0f8968ffffff         | jns                 0xffffff6e
            //   5f                   | pop                 edi
            //   5e                   | pop                 esi
            //   5d                   | pop                 ebp

        $sequence_6 = { 6812151110 6815111047 b815204712 50 50 68101a4712 }
            // n = 6, score = 300
            //   6812151110           | push                0x10111512
            //   6815111047           | push                0x47101115
            //   b815204712           | mov                 eax, 0x12472015
            //   50                   | push                eax
            //   50                   | push                eax
            //   68101a4712           | push                0x12471a10

        $sequence_7 = { 68???????? e8???????? 85c0 59 7513 68e8030000 }
            // n = 6, score = 300
            //   68????????           |                     
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   59                   | pop                 ecx
            //   7513                 | jne                 0x15
            //   68e8030000           | push                0x3e8

        $sequence_8 = { 73f6 8a47ff 240f 3c0c 7503 5a }
            // n = 6, score = 300
            //   73f6                 | jae                 0xfffffff8
            //   8a47ff               | mov                 al, byte ptr [edi - 1]
            //   240f                 | and                 al, 0xf
            //   3c0c                 | cmp                 al, 0xc
            //   7503                 | jne                 5
            //   5a                   | pop                 edx

        $sequence_9 = { 51 d9e0 dec1 dc45e0 }
            // n = 4, score = 300
            //   51                   | push                ecx
            //   d9e0                 | fchs                
            //   dec1                 | faddp               st(1)
            //   dc45e0               | fadd                qword ptr [ebp - 0x20]

    condition:
        7 of them and filesize < 335872
}