rule win_emdivi_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-04-08"
        version = "1"
        description = "Detects win.emdivi."
        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.emdivi"
        malpedia_rule_date = "20220405"
        malpedia_hash = "ecd38294bd47d5589be5cd5490dc8bb4804afc2a"
        malpedia_version = "20220411"
        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???????? c3 beff010000 56 8d85edfaffff 53 50 }
            // n = 7, score = 300
            //   e8????????           |                     
            //   c3                   | ret                 
            //   beff010000           | mov                 esi, 0x1ff
            //   56                   | push                esi
            //   8d85edfaffff         | lea                 eax, dword ptr [ebp - 0x513]
            //   53                   | push                ebx
            //   50                   | push                eax

        $sequence_1 = { 7504 83c60c 49 8d4601 6bc003 99 6a05 }
            // n = 7, score = 300
            //   7504                 | jne                 6
            //   83c60c               | add                 esi, 0xc
            //   49                   | dec                 ecx
            //   8d4601               | lea                 eax, dword ptr [esi + 1]
            //   6bc003               | imul                eax, eax, 3
            //   99                   | cdq                 
            //   6a05                 | push                5

        $sequence_2 = { 8945f8 8d45f8 50 8d45d0 50 8955fc }
            // n = 6, score = 300
            //   8945f8               | mov                 dword ptr [ebp - 8], eax
            //   8d45f8               | lea                 eax, dword ptr [ebp - 8]
            //   50                   | push                eax
            //   8d45d0               | lea                 eax, dword ptr [ebp - 0x30]
            //   50                   | push                eax
            //   8955fc               | mov                 dword ptr [ebp - 4], edx

        $sequence_3 = { 8b4df8 3bcf 7e08 8d7302 8bfb 66f3a5 }
            // n = 6, score = 300
            //   8b4df8               | mov                 ecx, dword ptr [ebp - 8]
            //   3bcf                 | cmp                 ecx, edi
            //   7e08                 | jle                 0xa
            //   8d7302               | lea                 esi, dword ptr [ebx + 2]
            //   8bfb                 | mov                 edi, ebx
            //   66f3a5               | rep movsd           dword ptr es:[edi], dword ptr [esi]

        $sequence_4 = { e8???????? 83c410 33ff 397df4 7409 }
            // n = 5, score = 300
            //   e8????????           |                     
            //   83c410               | add                 esp, 0x10
            //   33ff                 | xor                 edi, edi
            //   397df4               | cmp                 dword ptr [ebp - 0xc], edi
            //   7409                 | je                  0xb

        $sequence_5 = { 881f 59 47 8a06 }
            // n = 4, score = 300
            //   881f                 | mov                 byte ptr [edi], bl
            //   59                   | pop                 ecx
            //   47                   | inc                 edi
            //   8a06                 | mov                 al, byte ptr [esi]

        $sequence_6 = { c1ef03 c1e304 83e203 3355f8 33fb 03f7 8b7d08 }
            // n = 7, score = 300
            //   c1ef03               | shr                 edi, 3
            //   c1e304               | shl                 ebx, 4
            //   83e203               | and                 edx, 3
            //   3355f8               | xor                 edx, dword ptr [ebp - 8]
            //   33fb                 | xor                 edi, ebx
            //   03f7                 | add                 esi, edi
            //   8b7d08               | mov                 edi, dword ptr [ebp + 8]

        $sequence_7 = { 8801 0fb606 0fb65601 23c3 c1e004 }
            // n = 5, score = 300
            //   8801                 | mov                 byte ptr [ecx], al
            //   0fb606               | movzx               eax, byte ptr [esi]
            //   0fb65601             | movzx               edx, byte ptr [esi + 1]
            //   23c3                 | and                 eax, ebx
            //   c1e004               | shl                 eax, 4

        $sequence_8 = { 8975ec 8b03 8945f0 8b4304 8945f4 }
            // n = 5, score = 300
            //   8975ec               | mov                 dword ptr [ebp - 0x14], esi
            //   8b03                 | mov                 eax, dword ptr [ebx]
            //   8945f0               | mov                 dword ptr [ebp - 0x10], eax
            //   8b4304               | mov                 eax, dword ptr [ebx + 4]
            //   8945f4               | mov                 dword ptr [ebp - 0xc], eax

        $sequence_9 = { 0ad8 881f 59 47 807df43d 59 742b }
            // n = 7, score = 300
            //   0ad8                 | or                  bl, al
            //   881f                 | mov                 byte ptr [edi], bl
            //   59                   | pop                 ecx
            //   47                   | inc                 edi
            //   807df43d             | cmp                 byte ptr [ebp - 0xc], 0x3d
            //   59                   | pop                 ecx
            //   742b                 | je                  0x2d

    condition:
        7 of them and filesize < 581632
}