rule win_nymaim2_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2023-03-28"
        version = "1"
        description = "Detects win.nymaim2."
        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.nymaim2"
        malpedia_rule_date = "20230328"
        malpedia_hash = "9d2d75cef573c1c2d861f5197df8f563b05a305d"
        malpedia_version = "20230407"
        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 = { 56 e8???????? 8b4508 8b4dec 83c448 0fb7444354 ff3481 }
            // n = 7, score = 200
            //   56                   | push                esi
            //   e8????????           |                     
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8b4dec               | mov                 ecx, dword ptr [ebp - 0x14]
            //   83c448               | add                 esp, 0x48
            //   0fb7444354           | movzx               eax, word ptr [ebx + eax*2 + 0x54]
            //   ff3481               | push                dword ptr [ecx + eax*4]

        $sequence_1 = { 83780800 75c2 ff400c ebbd 8b5620 8b461c 8d4af8 }
            // n = 7, score = 200
            //   83780800             | cmp                 dword ptr [eax + 8], 0
            //   75c2                 | jne                 0xffffffc4
            //   ff400c               | inc                 dword ptr [eax + 0xc]
            //   ebbd                 | jmp                 0xffffffbf
            //   8b5620               | mov                 edx, dword ptr [esi + 0x20]
            //   8b461c               | mov                 eax, dword ptr [esi + 0x1c]
            //   8d4af8               | lea                 ecx, [edx - 8]

        $sequence_2 = { e8???????? 8d4de8 c645fc07 e8???????? 395dd8 895d08 7e51 }
            // n = 7, score = 200
            //   e8????????           |                     
            //   8d4de8               | lea                 ecx, [ebp - 0x18]
            //   c645fc07             | mov                 byte ptr [ebp - 4], 7
            //   e8????????           |                     
            //   395dd8               | cmp                 dword ptr [ebp - 0x28], ebx
            //   895d08               | mov                 dword ptr [ebp + 8], ebx
            //   7e51                 | jle                 0x53

        $sequence_3 = { 83c440 6a50 68???????? e8???????? 6a60 68???????? e8???????? }
            // n = 7, score = 200
            //   83c440               | add                 esp, 0x40
            //   6a50                 | push                0x50
            //   68????????           |                     
            //   e8????????           |                     
            //   6a60                 | push                0x60
            //   68????????           |                     
            //   e8????????           |                     

        $sequence_4 = { c1f808 99 2bc2 d1f8 40 c1e008 8901 }
            // n = 7, score = 200
            //   c1f808               | sar                 eax, 8
            //   99                   | cdq                 
            //   2bc2                 | sub                 eax, edx
            //   d1f8                 | sar                 eax, 1
            //   40                   | inc                 eax
            //   c1e008               | shl                 eax, 8
            //   8901                 | mov                 dword ptr [ecx], eax

        $sequence_5 = { 8965e4 50 e8???????? 59 8d45e8 50 }
            // n = 6, score = 200
            //   8965e4               | mov                 dword ptr [ebp - 0x1c], esp
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   8d45e8               | lea                 eax, [ebp - 0x18]
            //   50                   | push                eax

        $sequence_6 = { 8965f0 50 e8???????? 59 8d45f0 50 }
            // n = 6, score = 200
            //   8965f0               | mov                 dword ptr [ebp - 0x10], esp
            //   50                   | push                eax
            //   e8????????           |                     
            //   59                   | pop                 ecx
            //   8d45f0               | lea                 eax, [ebp - 0x10]
            //   50                   | push                eax

        $sequence_7 = { 68eb000000 895dfc e8???????? 8bc8 c645fc02 e8???????? 51 }
            // n = 7, score = 200
            //   68eb000000           | push                0xeb
            //   895dfc               | mov                 dword ptr [ebp - 4], ebx
            //   e8????????           |                     
            //   8bc8                 | mov                 ecx, eax
            //   c645fc02             | mov                 byte ptr [ebp - 4], 2
            //   e8????????           |                     
            //   51                   | push                ecx

        $sequence_8 = { 681d040000 8d4ddc e8???????? 8bc8 c745fc12000000 e8???????? 8945bc }
            // n = 7, score = 200
            //   681d040000           | push                0x41d
            //   8d4ddc               | lea                 ecx, [ebp - 0x24]
            //   e8????????           |                     
            //   8bc8                 | mov                 ecx, eax
            //   c745fc12000000       | mov                 dword ptr [ebp - 4], 0x12
            //   e8????????           |                     
            //   8945bc               | mov                 dword ptr [ebp - 0x44], eax

        $sequence_9 = { c1e004 50 ff7604 53 e8???????? 8b4608 8bcf }
            // n = 7, score = 200
            //   c1e004               | shl                 eax, 4
            //   50                   | push                eax
            //   ff7604               | push                dword ptr [esi + 4]
            //   53                   | push                ebx
            //   e8????????           |                     
            //   8b4608               | mov                 eax, dword ptr [esi + 8]
            //   8bcf                 | mov                 ecx, edi

    condition:
        7 of them and filesize < 753664
}