rule win_conficker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2026-09-17"
        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 = "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 = { ff15???????? 3345f8 33c7 33c6 50 ff15???????? }
            // n = 6, score = 300
            //   ff15????????         |                     
            //   3345f8               | xor                 eax, dword ptr [ebp - 8]
            //   33c7                 | xor                 eax, edi
            //   33c6                 | xor                 eax, esi
            //   50                   | push                eax
            //   ff15????????         |                     

        $sequence_1 = { c1e805 8b0482 83e11f d3e8 }
            // n = 4, score = 300
            //   c1e805               | shr                 eax, 5
            //   8b0482               | mov                 eax, dword ptr [edx + eax*4]
            //   83e11f               | and                 ecx, 0x1f
            //   d3e8                 | shr                 eax, cl

        $sequence_2 = { c3 55 8bec 83ec20 8b0d???????? a1???????? }
            // n = 6, score = 300
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp
            //   83ec20               | sub                 esp, 0x20
            //   8b0d????????         |                     
            //   a1????????           |                     

        $sequence_3 = { 3c08 7422 42 3c04 7415 42 }
            // n = 6, score = 300
            //   3c08                 | cmp                 al, 8
            //   7422                 | je                  0x24
            //   42                   | inc                 edx
            //   3c04                 | cmp                 al, 4
            //   7415                 | je                  0x17
            //   42                   | inc                 edx

        $sequence_4 = { 8945e4 8365fc00 85c0 7420 }
            // n = 4, score = 300
            //   8945e4               | mov                 dword ptr [ebp - 0x1c], eax
            //   8365fc00             | and                 dword ptr [ebp - 4], 0
            //   85c0                 | test                eax, eax
            //   7420                 | je                  0x22

        $sequence_5 = { 8b5d0c 8a1c1e 02da 8d7c8808 }
            // n = 4, score = 300
            //   8b5d0c               | mov                 ebx, dword ptr [ebp + 0xc]
            //   8a1c1e               | mov                 bl, byte ptr [esi + ebx]
            //   02da                 | add                 bl, dl
            //   8d7c8808             | lea                 edi, [eax + ecx*4 + 8]

        $sequence_6 = { 74db 81c751000000 3c0a 74d4 }
            // n = 4, score = 300
            //   74db                 | je                  0xffffffdd
            //   81c751000000         | add                 edi, 0x51
            //   3c0a                 | cmp                 al, 0xa
            //   74d4                 | je                  0xffffffd6

        $sequence_7 = { 42 ebe4 f60638 75a8 b008 d0ef 1400 }
            // n = 7, score = 300
            //   42                   | inc                 edx
            //   ebe4                 | jmp                 0xffffffe6
            //   f60638               | test                byte ptr [esi], 0x38
            //   75a8                 | jne                 0xffffffaa
            //   b008                 | mov                 al, 8
            //   d0ef                 | shr                 bh, 1
            //   1400                 | adc                 al, 0

        $sequence_8 = { 61 c3 ac 88c4 c0e807 7212 7414 }
            // n = 7, score = 300
            //   61                   | popal               
            //   c3                   | ret                 
            //   ac                   | lodsb               al, byte ptr [esi]
            //   88c4                 | mov                 ah, al
            //   c0e807               | shr                 al, 7
            //   7212                 | jb                  0x14
            //   7414                 | je                  0x16

        $sequence_9 = { e2f9 ff7510 ff7508 e8???????? 85c0 59 }
            // n = 6, score = 300
            //   e2f9                 | loop                0xfffffffb
            //   ff7510               | push                dword ptr [ebp + 0x10]
            //   ff7508               | push                dword ptr [ebp + 8]
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   59                   | pop                 ecx

    condition:
        7 of them and filesize < 335872
}