rule win_tinyloader_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.tinyloader"
        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 = { ebe6 8b5d00 8b4308 83f800 }
            // n = 4, score = 100
            //   ebe6                 | jmp                 0xffffffe8
            //   8b5d00               | mov                 ebx, dword ptr [ebp]
            //   8b4308               | mov                 eax, dword ptr [ebx + 8]
            //   83f800               | cmp                 eax, 0

        $sequence_1 = { 31d2 8b4d00 8b4904 8b5500 }
            // n = 4, score = 100
            //   31d2                 | xor                 edx, edx
            //   8b4d00               | mov                 ecx, dword ptr [ebp]
            //   8b4904               | mov                 ecx, dword ptr [ecx + 4]
            //   8b5500               | mov                 edx, dword ptr [ebp]

        $sequence_2 = { 90 89c6 90 0500400100 90 31db }
            // n = 6, score = 100
            //   90                   | nop                 
            //   89c6                 | mov                 esi, eax
            //   90                   | nop                 
            //   0500400100           | add                 eax, 0x14000
            //   90                   | nop                 
            //   31db                 | xor                 ebx, ebx

        $sequence_3 = { 8938 90 81fb04030000 730d 90 83c004 }
            // n = 6, score = 100
            //   8938                 | mov                 dword ptr [eax], edi
            //   90                   | nop                 
            //   81fb04030000         | cmp                 ebx, 0x304
            //   730d                 | jae                 0xf
            //   90                   | nop                 
            //   83c004               | add                 eax, 4

        $sequence_4 = { 8985a0050000 0500200000 8985a8050000 0500080000 894508 }
            // n = 5, score = 100
            //   8985a0050000         | mov                 dword ptr [ebp + 0x5a0], eax
            //   0500200000           | add                 eax, 0x2000
            //   8985a8050000         | mov                 dword ptr [ebp + 0x5a8], eax
            //   0500080000           | add                 eax, 0x800
            //   894508               | mov                 dword ptr [ebp + 8], eax

        $sequence_5 = { 90 8938 90 81fb04030000 }
            // n = 4, score = 100
            //   90                   | nop                 
            //   8938                 | mov                 dword ptr [eax], edi
            //   90                   | nop                 
            //   81fb04030000         | cmp                 ebx, 0x304

        $sequence_6 = { 0050ff 15???????? c705????????00010000 68???????? 68???????? ff15???????? }
            // n = 6, score = 100
            // 
            //   15????????           |                     
            //   c705????????00010000     |     
            //   68????????           |                     
            //   68????????           |                     
            //   ff15????????         |                     

        $sequence_7 = { 90 813890909090 740e 83fb00 7509 90 3108 }
            // n = 7, score = 100
            //   90                   | nop                 
            //   813890909090         | cmp                 dword ptr [eax], 0x90909090
            //   740e                 | je                  0x10
            //   83fb00               | cmp                 ebx, 0
            //   7509                 | jne                 0xb
            //   90                   | nop                 
            //   3108                 | xor                 dword ptr [eax], ecx

        $sequence_8 = { 731a 83f800 7615 8b5510 01da 8b12 8b4500 }
            // n = 7, score = 100
            //   731a                 | jae                 0x1c
            //   83f800               | cmp                 eax, 0
            //   7615                 | jbe                 0x17
            //   8b5510               | mov                 edx, dword ptr [ebp + 0x10]
            //   01da                 | add                 edx, ebx
            //   8b12                 | mov                 edx, dword ptr [edx]
            //   8b4500               | mov                 eax, dword ptr [ebp]

        $sequence_9 = { 8985b0020000 83bdb002000000 7502 eb1f }
            // n = 4, score = 100
            //   8985b0020000         | mov                 dword ptr [ebp + 0x2b0], eax
            //   83bdb002000000       | cmp                 dword ptr [ebp + 0x2b0], 0
            //   7502                 | jne                 4
            //   eb1f                 | jmp                 0x21

        $sequence_10 = { 0500080000 894520 ffb5a0050000 6802020000 }
            // n = 4, score = 100
            //   0500080000           | add                 eax, 0x800
            //   894520               | mov                 dword ptr [ebp + 0x20], eax
            //   ffb5a0050000         | push                dword ptr [ebp + 0x5a0]
            //   6802020000           | push                0x202

        $sequence_11 = { 53 68656c6c45 7865 637574 6541 0050ff }
            // n = 6, score = 100
            //   53                   | push                ebx
            //   68656c6c45           | push                0x456c6c65
            //   7865                 | js                  0x67
            //   637574               | arpl                word ptr [ebp + 0x74], si
            //   6541                 | inc                 ecx
            //   0050ff               | add                 byte ptr [eax - 1], dl

        $sequence_12 = { 6a40 6800300000 6800800200 6a00 ff15???????? 90 8b1d???????? }
            // n = 7, score = 100
            //   6a40                 | push                0x40
            //   6800300000           | push                0x3000
            //   6800800200           | push                0x28000
            //   6a00                 | push                0
            //   ff15????????         |                     
            //   90                   | nop                 
            //   8b1d????????         |                     

        $sequence_13 = { 018558080000 83bd580800000c 7302 ebc3 8b5d00 8b4308 3b8558080000 }
            // n = 7, score = 100
            //   018558080000         | add                 dword ptr [ebp + 0x858], eax
            //   83bd580800000c       | cmp                 dword ptr [ebp + 0x858], 0xc
            //   7302                 | jae                 4
            //   ebc3                 | jmp                 0xffffffc5
            //   8b5d00               | mov                 ebx, dword ptr [ebp]
            //   8b4308               | mov                 eax, dword ptr [ebx + 8]
            //   3b8558080000         | cmp                 eax, dword ptr [ebp + 0x858]

        $sequence_14 = { 6a40 6800300000 6800400100 6a00 }
            // n = 4, score = 100
            //   6a40                 | push                0x40
            //   6800300000           | push                0x3000
            //   6800400100           | push                0x14000
            //   6a00                 | push                0

        $sequence_15 = { 90 8b1d???????? 90 895830 90 8b1d???????? 90 }
            // n = 7, score = 100
            //   90                   | nop                 
            //   8b1d????????         |                     
            //   90                   | nop                 
            //   895830               | mov                 dword ptr [eax + 0x30], ebx
            //   90                   | nop                 
            //   8b1d????????         |                     
            //   90                   | nop                 

    condition:
        7 of them and filesize < 40960
}