rule win_koadic_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-05-30"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.4.0"
        tool_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.koadic"
        malpedia_rule_date = "20200529"
        malpedia_hash = "92c362319514e5a6da26204961446caa3a8b32a8"
        malpedia_version = "20200529"
        malpedia_license = "CC BY-NC-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 / approach 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 = { 5e c20400 8b4114 56 3b4124 7d14 8b5104 }
            // n = 7, score = 100
            //   5e                   | pop                 esi
            //   c20400               | ret                 4
            //   8b4114               | mov                 eax, dword ptr [ecx + 0x14]
            //   56                   | push                esi
            //   3b4124               | cmp                 eax, dword ptr [ecx + 0x24]
            //   7d14                 | jge                 0x16
            //   8b5104               | mov                 edx, dword ptr [ecx + 4]

        $sequence_1 = { 394814 744e eb03 8b5d10 ff36 e8???????? 8b4e08 }
            // n = 7, score = 100
            //   394814               | cmp                 dword ptr [eax + 0x14], ecx
            //   744e                 | je                  0x50
            //   eb03                 | jmp                 5
            //   8b5d10               | mov                 ebx, dword ptr [ebp + 0x10]
            //   ff36                 | push                dword ptr [esi]
            //   e8????????           |                     
            //   8b4e08               | mov                 ecx, dword ptr [esi + 8]

        $sequence_2 = { ff750c ff7508 53 e8???????? 99 83c40c 3b06 }
            // n = 7, score = 100
            //   ff750c               | push                dword ptr [ebp + 0xc]
            //   ff7508               | push                dword ptr [ebp + 8]
            //   53                   | push                ebx
            //   e8????????           |                     
            //   99                   | cdq                 
            //   83c40c               | add                 esp, 0xc
            //   3b06                 | cmp                 eax, dword ptr [esi]

        $sequence_3 = { 660fb602 668945fc 0fb74dfc 81e180000000 7517 8b55f8 }
            // n = 6, score = 100
            //   660fb602             | movzx               ax, byte ptr [edx]
            //   668945fc             | mov                 word ptr [ebp - 4], ax
            //   0fb74dfc             | movzx               ecx, word ptr [ebp - 4]
            //   81e180000000         | and                 ecx, 0x80
            //   7517                 | jne                 0x19
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]

        $sequence_4 = { c20400 8b442404 8b4010 c20400 8b442404 83600800 c6403001 }
            // n = 7, score = 100
            //   c20400               | ret                 4
            //   8b442404             | mov                 eax, dword ptr [esp + 4]
            //   8b4010               | mov                 eax, dword ptr [eax + 0x10]
            //   c20400               | ret                 4
            //   8b442404             | mov                 eax, dword ptr [esp + 4]
            //   83600800             | and                 dword ptr [eax + 8], 0
            //   c6403001             | mov                 byte ptr [eax + 0x30], 1

        $sequence_5 = { 75ee 5b 8b4630 56 55 8928 ff35???????? }
            // n = 7, score = 100
            //   75ee                 | jne                 0xfffffff0
            //   5b                   | pop                 ebx
            //   8b4630               | mov                 eax, dword ptr [esi + 0x30]
            //   56                   | push                esi
            //   55                   | push                ebp
            //   8928                 | mov                 dword ptr [eax], ebp
            //   ff35????????         |                     

        $sequence_6 = { 8b15???????? e8???????? 8b54241c e8???????? 8b542428 e8???????? 8b2d???????? }
            // n = 7, score = 100
            //   8b15????????         |                     
            //   e8????????           |                     
            //   8b54241c             | mov                 edx, dword ptr [esp + 0x1c]
            //   e8????????           |                     
            //   8b542428             | mov                 edx, dword ptr [esp + 0x28]
            //   e8????????           |                     
            //   8b2d????????         |                     

        $sequence_7 = { 83feff 0f8580fdffff 8bc8 8b450c 5e 3bc8 7d1d }
            // n = 7, score = 100
            //   83feff               | cmp                 esi, -1
            //   0f8580fdffff         | jne                 0xfffffd86
            //   8bc8                 | mov                 ecx, eax
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   5e                   | pop                 esi
            //   3bc8                 | cmp                 ecx, eax
            //   7d1d                 | jge                 0x1f

        $sequence_8 = { 8b54241c e8???????? 8b542428 e8???????? 8b2d???????? 8d450c 50 }
            // n = 7, score = 100
            //   8b54241c             | mov                 edx, dword ptr [esp + 0x1c]
            //   e8????????           |                     
            //   8b542428             | mov                 edx, dword ptr [esp + 0x28]
            //   e8????????           |                     
            //   8b2d????????         |                     
            //   8d450c               | lea                 eax, [ebp + 0xc]
            //   50                   | push                eax

        $sequence_9 = { a3???????? e8???????? 6800040000 68???????? 56 6a07 6a08 }
            // n = 7, score = 100
            //   a3????????           |                     
            //   e8????????           |                     
            //   6800040000           | push                0x400
            //   68????????           |                     
            //   56                   | push                esi
            //   6a07                 | push                7
            //   6a08                 | push                8

    condition:
        7 of them and filesize < 180224
}