rule win_tinyloader_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-12-22"
        version = "1"
        description = "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.tinyloader"
        malpedia_rule_date = "20201222"
        malpedia_hash = "30354d830a29f0fbd3714d93d94dea941d77a130"
        malpedia_version = "20201023"
        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 = { c1c010 6689c8 90 6a40 6800300000 6800800200 }
            // n = 6, score = 100
            //   c1c010               | rol                 eax, 0x10
            //   6689c8               | mov                 ax, cx
            //   90                   | nop                 
            //   6a40                 | push                0x40
            //   6800300000           | push                0x3000
            //   6800800200           | push                0x28000

        $sequence_1 = { ff15???????? e8???????? 53 68656c6c45 7865 }
            // n = 5, score = 100
            //   ff15????????         |                     
            //   e8????????           |                     
            //   53                   | push                ebx
            //   68656c6c45           | push                0x456c6c65
            //   7865                 | js                  0x67

        $sequence_2 = { 637574 6541 0050ff 15???????? c705????????00010000 68???????? 68???????? }
            // n = 7, score = 100
            //   637574               | arpl                word ptr [ebp + 0x74], si
            //   6541                 | inc                 ecx
            //   0050ff               | add                 byte ptr [eax - 1], dl
            //   15????????           |                     
            //   c705????????00010000     |     
            //   68????????           |                     
            //   68????????           |                     

        $sequence_3 = { 0500200000 8985a8050000 0500080000 894508 0500200000 }
            // n = 5, score = 100
            //   0500200000           | add                 eax, 0x2000
            //   8985a8050000         | mov                 dword ptr [ebp + 0x5a8], eax
            //   0500080000           | add                 eax, 0x800
            //   894508               | mov                 dword ptr [ebp + 8], eax
            //   0500200000           | add                 eax, 0x2000

        $sequence_4 = { 81fb04030000 730d 90 83c004 90 }
            // n = 5, score = 100
            //   81fb04030000         | cmp                 ebx, 0x304
            //   730d                 | jae                 0xf
            //   90                   | nop                 
            //   83c004               | add                 eax, 4
            //   90                   | nop                 

        $sequence_5 = { f7d2 f7d1 5b 89d0 c1c010 6689c8 90 }
            // n = 7, score = 100
            //   f7d2                 | not                 edx
            //   f7d1                 | not                 ecx
            //   5b                   | pop                 ebx
            //   89d0                 | mov                 eax, edx
            //   c1c010               | rol                 eax, 0x10
            //   6689c8               | mov                 ax, cx
            //   90                   | nop                 

        $sequence_6 = { 7402 eb42 8b4500 83c00c ffd0 31db }
            // n = 6, score = 100
            //   7402                 | je                  4
            //   eb42                 | jmp                 0x44
            //   8b4500               | mov                 eax, dword ptr [ebp]
            //   83c00c               | add                 eax, 0xc
            //   ffd0                 | call                eax
            //   31db                 | xor                 ebx, ebx

        $sequence_7 = { 8b4500 8b8000040000 83f80c 7702 eb28 83e80c 39c3 }
            // n = 7, score = 100
            //   8b4500               | mov                 eax, dword ptr [ebp]
            //   8b8000040000         | mov                 eax, dword ptr [eax + 0x400]
            //   83f80c               | cmp                 eax, 0xc
            //   7702                 | ja                  4
            //   eb28                 | jmp                 0x2a
            //   83e80c               | sub                 eax, 0xc
            //   39c3                 | cmp                 ebx, eax

        $sequence_8 = { 83c00c 891418 83c304 ebc8 ffb5b8050000 }
            // n = 5, score = 100
            //   83c00c               | add                 eax, 0xc
            //   891418               | mov                 dword ptr [eax + ebx], edx
            //   83c304               | add                 ebx, 4
            //   ebc8                 | jmp                 0xffffffca
            //   ffb5b8050000         | push                dword ptr [ebp + 0x5b8]

        $sequence_9 = { 83bd4005000001 7502 eb0c c7854005000000000084 }
            // n = 4, score = 100
            //   83bd4005000001       | cmp                 dword ptr [ebp + 0x540], 1
            //   7502                 | jne                 4
            //   eb0c                 | jmp                 0xe
            //   c7854005000000000084     | mov    dword ptr [ebp + 0x540], 0x84000000

        $sequence_10 = { ff15???????? 90 8b1d???????? 90 8998f8070000 }
            // n = 5, score = 100
            //   ff15????????         |                     
            //   90                   | nop                 
            //   8b1d????????         |                     
            //   90                   | nop                 
            //   8998f8070000         | mov                 dword ptr [eax + 0x7f8], ebx

        $sequence_11 = { 813890909090 740e 83fb00 7509 90 3108 90 }
            // n = 7, score = 100
            //   813890909090         | cmp                 dword ptr [eax], 0x90909090
            //   740e                 | je                  0x10
            //   83fb00               | cmp                 ebx, 0
            //   7509                 | jne                 0xb
            //   90                   | nop                 
            //   3108                 | xor                 dword ptr [eax], ecx
            //   90                   | nop                 

        $sequence_12 = { 6a00 ff33 ff7500 ffb5b8050000 ff15???????? }
            // n = 5, score = 100
            //   6a00                 | push                0
            //   ff33                 | push                dword ptr [ebx]
            //   ff7500               | push                dword ptr [ebp]
            //   ffb5b8050000         | push                dword ptr [ebp + 0x5b8]
            //   ff15????????         |                     

        $sequence_13 = { 6a40 6800300000 6800800200 6a00 ff15???????? 90 }
            // n = 6, score = 100
            //   6a40                 | push                0x40
            //   6800300000           | push                0x3000
            //   6800800200           | push                0x28000
            //   6a00                 | push                0
            //   ff15????????         |                     
            //   90                   | nop                 

        $sequence_14 = { e9???????? 8b5d00 81c300040000 6a00 }
            // n = 4, score = 100
            //   e9????????           |                     
            //   8b5d00               | mov                 ebx, dword ptr [ebp]
            //   81c300040000         | add                 ebx, 0x400
            //   6a00                 | push                0

        $sequence_15 = { 8b5d00 894304 8b5d00 81c300040000 }
            // n = 4, score = 100
            //   8b5d00               | mov                 ebx, dword ptr [ebp]
            //   894304               | mov                 dword ptr [ebx + 4], eax
            //   8b5d00               | mov                 ebx, dword ptr [ebp]
            //   81c300040000         | add                 ebx, 0x400

    condition:
        7 of them and filesize < 40960
}