rule win_virut_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2021-06-10"
        version = "1"
        description = "Detects win.virut."
        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.virut"
        malpedia_rule_date = "20210604"
        malpedia_hash = "be09d5d71e77373c0f538068be31a2ad4c69cfbd"
        malpedia_version = "20210616"
        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 = { e8???????? 57 53 4f }
            // n = 4, score = 200
            //   e8????????           |                     
            //   57                   | push                edi
            //   53                   | push                ebx
            //   4f                   | dec                 edi

        $sequence_1 = { c744241c00004000 3bc3 7438 83c00f eb01 }
            // n = 5, score = 200
            //   c744241c00004000     | mov                 dword ptr [esp + 0x1c], 0x400000
            //   3bc3                 | cmp                 eax, ebx
            //   7438                 | je                  0x3a
            //   83c00f               | add                 eax, 0xf
            //   eb01                 | jmp                 3

        $sequence_2 = { 6801040000 8d8424fc050000 53 50 e8???????? 83c40c }
            // n = 6, score = 200
            //   6801040000           | push                0x401
            //   8d8424fc050000       | lea                 eax, dword ptr [esp + 0x5fc]
            //   53                   | push                ebx
            //   50                   | push                eax
            //   e8????????           |                     
            //   83c40c               | add                 esp, 0xc

        $sequence_3 = { 8bd4 50 54 6a40 51 52 }
            // n = 6, score = 200
            //   8bd4                 | mov                 edx, esp
            //   50                   | push                eax
            //   54                   | push                esp
            //   6a40                 | push                0x40
            //   51                   | push                ecx
            //   52                   | push                edx

        $sequence_4 = { 3bc3 0f8484020000 8b400c 8b00 8b30 3bf3 0f8475020000 }
            // n = 7, score = 200
            //   3bc3                 | cmp                 eax, ebx
            //   0f8484020000         | je                  0x28a
            //   8b400c               | mov                 eax, dword ptr [eax + 0xc]
            //   8b00                 | mov                 eax, dword ptr [eax]
            //   8b30                 | mov                 esi, dword ptr [eax]
            //   3bf3                 | cmp                 esi, ebx
            //   0f8475020000         | je                  0x27b

        $sequence_5 = { ff742424 ff15???????? 3bc3 7e1a }
            // n = 4, score = 200
            //   ff742424             | push                dword ptr [esp + 0x24]
            //   ff15????????         |                     
            //   3bc3                 | cmp                 eax, ebx
            //   7e1a                 | jle                 0x1c

        $sequence_6 = { 8d85ecfbffff ff7510 68???????? 50 ff15???????? }
            // n = 5, score = 200
            //   8d85ecfbffff         | lea                 eax, dword ptr [ebp - 0x414]
            //   ff7510               | push                dword ptr [ebp + 0x10]
            //   68????????           |                     
            //   50                   | push                eax
            //   ff15????????         |                     

        $sequence_7 = { 8944241c 3acb 75df ff74241c 6a40 ff15???????? }
            // n = 6, score = 200
            //   8944241c             | mov                 dword ptr [esp + 0x1c], eax
            //   3acb                 | cmp                 cl, bl
            //   75df                 | jne                 0xffffffe1
            //   ff74241c             | push                dword ptr [esp + 0x1c]
            //   6a40                 | push                0x40
            //   ff15????????         |                     

        $sequence_8 = { 33d2 8bcf 52 f6d9 52 83e103 6a40 }
            // n = 7, score = 200
            //   33d2                 | xor                 edx, edx
            //   8bcf                 | mov                 ecx, edi
            //   52                   | push                edx
            //   f6d9                 | neg                 cl
            //   52                   | push                edx
            //   83e103               | and                 ecx, 3
            //   6a40                 | push                0x40

        $sequence_9 = { 745b 50 54 6804010000 57 ffb42420020000 }
            // n = 6, score = 200
            //   745b                 | je                  0x5d
            //   50                   | push                eax
            //   54                   | push                esp
            //   6804010000           | push                0x104
            //   57                   | push                edi
            //   ffb42420020000       | push                dword ptr [esp + 0x220]

        $sequence_10 = { 51 54 51 51 }
            // n = 4, score = 200
            //   51                   | push                ecx
            //   54                   | push                esp
            //   51                   | push                ecx
            //   51                   | push                ecx

        $sequence_11 = { 83f800 7c19 60 e8???????? 8b542430 5d 8b1a }
            // n = 7, score = 200
            //   83f800               | cmp                 eax, 0
            //   7c19                 | jl                  0x1b
            //   60                   | pushal              
            //   e8????????           |                     
            //   8b542430             | mov                 edx, dword ptr [esp + 0x30]
            //   5d                   | pop                 ebp
            //   8b1a                 | mov                 ebx, dword ptr [edx]

        $sequence_12 = { 57 6a44 58 8d9704010000 ab }
            // n = 5, score = 200
            //   57                   | push                edi
            //   6a44                 | push                0x44
            //   58                   | pop                 eax
            //   8d9704010000         | lea                 edx, dword ptr [edi + 0x104]
            //   ab                   | stosd               dword ptr es:[edi], eax

        $sequence_13 = { ffd6 83f8ff 0f8573030000 6800100000 }
            // n = 4, score = 200
            //   ffd6                 | call                esi
            //   83f8ff               | cmp                 eax, -1
            //   0f8573030000         | jne                 0x379
            //   6800100000           | push                0x1000

        $sequence_14 = { 8bcc 6a00 8bc4 6a00 6800000008 6a40 51 }
            // n = 7, score = 200
            //   8bcc                 | mov                 ecx, esp
            //   6a00                 | push                0
            //   8bc4                 | mov                 eax, esp
            //   6a00                 | push                0
            //   6800000008           | push                0x8000000
            //   6a40                 | push                0x40
            //   51                   | push                ecx

        $sequence_15 = { 69c06d4ec641 0539300000 a3???????? c1e80a c3 55 }
            // n = 6, score = 200
            //   69c06d4ec641         | imul                eax, eax, 0x41c64e6d
            //   0539300000           | add                 eax, 0x3039
            //   a3????????           |                     
            //   c1e80a               | shr                 eax, 0xa
            //   c3                   | ret                 
            //   55                   | push                ebp

    condition:
        7 of them and filesize < 98304
}