rule win_conficker_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        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 = "20230328"
        malpedia_hash = "9d2d75cef573c1c2d861f5197df8f563b05a305d"
        malpedia_version = "20230407"
        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 = { eb02 33db 53 53 6a02 53 }
            // n = 6, score = 300
            //   eb02                 | jmp                 4
            //   33db                 | xor                 ebx, ebx
            //   53                   | push                ebx
            //   53                   | push                ebx
            //   6a02                 | push                2
            //   53                   | push                ebx

        $sequence_1 = { 4a 4a 60 b066 f2ae 61 }
            // n = 6, score = 300
            //   4a                   | dec                 edx
            //   4a                   | dec                 edx
            //   60                   | pushal              
            //   b066                 | mov                 al, 0x66
            //   f2ae                 | repne scasb         al, byte ptr es:[edi]
            //   61                   | popal               

        $sequence_2 = { 8d7f04 e2f9 ff7510 ff7508 }
            // n = 4, score = 300
            //   8d7f04               | lea                 edi, [edi + 4]
            //   e2f9                 | loop                0xfffffffb
            //   ff7510               | push                dword ptr [ebp + 0x10]
            //   ff7508               | push                dword ptr [ebp + 8]

        $sequence_3 = { 85ff 7e17 ff15???????? 6a1a 99 }
            // n = 5, score = 300
            //   85ff                 | test                edi, edi
            //   7e17                 | jle                 0x19
            //   ff15????????         |                     
            //   6a1a                 | push                0x1a
            //   99                   | cdq                 

        $sequence_4 = { 23cf dec1 8945e8 894dec 51 dd5df0 51 }
            // n = 7, score = 300
            //   23cf                 | and                 ecx, edi
            //   dec1                 | faddp               st(1)
            //   8945e8               | mov                 dword ptr [ebp - 0x18], eax
            //   894dec               | mov                 dword ptr [ebp - 0x14], ecx
            //   51                   | push                ecx
            //   dd5df0               | fstp                qword ptr [ebp - 0x10]
            //   51                   | push                ecx

        $sequence_5 = { bfffffff7f 23d7 8945f0 8955f4 df6df0 be00000080 2175fc }
            // n = 7, score = 300
            //   bfffffff7f           | mov                 edi, 0x7fffffff
            //   23d7                 | and                 edx, edi
            //   8945f0               | mov                 dword ptr [ebp - 0x10], eax
            //   8955f4               | mov                 dword ptr [ebp - 0xc], edx
            //   df6df0               | fild                qword ptr [ebp - 0x10]
            //   be00000080           | mov                 esi, 0x80000000
            //   2175fc               | and                 dword ptr [ebp - 4], esi

        $sequence_6 = { 8d7604 8d7f04 e2f4 4a 0f8968ffffff 5f }
            // n = 6, score = 300
            //   8d7604               | lea                 esi, [esi + 4]
            //   8d7f04               | lea                 edi, [edi + 4]
            //   e2f4                 | loop                0xfffffff6
            //   4a                   | dec                 edx
            //   0f8968ffffff         | jns                 0xffffff6e
            //   5f                   | pop                 edi

        $sequence_7 = { 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_8 = { 48 79e5 33c0 5e c3 55 8bec }
            // n = 7, score = 300
            //   48                   | dec                 eax
            //   79e5                 | jns                 0xffffffe7
            //   33c0                 | xor                 eax, eax
            //   5e                   | pop                 esi
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   8bec                 | mov                 ebp, esp

        $sequence_9 = { c3 ac 88c4 c0e807 7212 }
            // n = 5, score = 300
            //   c3                   | ret                 
            //   ac                   | lodsb               al, byte ptr [esi]
            //   88c4                 | mov                 ah, al
            //   c0e807               | shr                 al, 7
            //   7212                 | jb                  0x14

    condition:
        7 of them and filesize < 335872
}