rule win_nymaim_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2021-06-10"
        version = "1"
        description = "Detects win.nymaim."
        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.nymaim"
        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 = { 89d8 01c8 31d2 f7f7 }
            // n = 4, score = 1800
            //   89d8                 | mov                 eax, ebx
            //   01c8                 | add                 eax, ecx
            //   31d2                 | xor                 edx, edx
            //   f7f7                 | div                 edi

        $sequence_1 = { f7f7 92 31d2 bf64000000 }
            // n = 4, score = 1700
            //   f7f7                 | div                 edi
            //   92                   | xchg                eax, edx
            //   31d2                 | xor                 edx, edx
            //   bf64000000           | mov                 edi, 0x64

        $sequence_2 = { 09c0 0f94c1 09c8 6bc064 }
            // n = 4, score = 1700
            //   09c0                 | or                  eax, eax
            //   0f94c1               | sete                cl
            //   09c8                 | or                  eax, ecx
            //   6bc064               | imul                eax, eax, 0x64

        $sequence_3 = { 010d???????? 8b1d???????? 011d???????? c1eb13 }
            // n = 4, score = 1600
            //   010d????????         |                     
            //   8b1d????????         |                     
            //   011d????????         |                     
            //   c1eb13               | shr                 ebx, 0x13

        $sequence_4 = { 31c3 891d???????? 89d8 01c8 }
            // n = 4, score = 1600
            //   31c3                 | xor                 ebx, eax
            //   891d????????         |                     
            //   89d8                 | mov                 eax, ebx
            //   01c8                 | add                 eax, ecx

        $sequence_5 = { e8???????? 83f800 7405 e8???????? }
            // n = 4, score = 1600
            //   e8????????           |                     
            //   83f800               | cmp                 eax, 0
            //   7405                 | je                  7
            //   e8????????           |                     

        $sequence_6 = { 31c9 38f0 83d100 38d0 83d900 }
            // n = 5, score = 1600
            //   31c9                 | xor                 ecx, ecx
            //   38f0                 | cmp                 al, dh
            //   83d100               | adc                 ecx, 0
            //   38d0                 | cmp                 al, dl
            //   83d900               | sbb                 ecx, 0

        $sequence_7 = { 31d2 bf64000000 f7f7 5b }
            // n = 4, score = 1600
            //   31d2                 | xor                 edx, edx
            //   bf64000000           | mov                 edi, 0x64
            //   f7f7                 | div                 edi
            //   5b                   | pop                 ebx

        $sequence_8 = { 38d0 83d900 c1e105 01c8 }
            // n = 4, score = 1600
            //   38d0                 | cmp                 al, dl
            //   83d900               | sbb                 ecx, 0
            //   c1e105               | shl                 ecx, 5
            //   01c8                 | add                 eax, ecx

        $sequence_9 = { 89ca 83e103 c1e103 89d8 }
            // n = 4, score = 1600
            //   89ca                 | mov                 edx, ecx
            //   83e103               | and                 ecx, 3
            //   c1e103               | shl                 ecx, 3
            //   89d8                 | mov                 eax, ebx

        $sequence_10 = { 00d3 8a16 301e 46 01fb }
            // n = 5, score = 1300
            //   00d3                 | add                 bl, dl
            //   8a16                 | mov                 dl, byte ptr [esi]
            //   301e                 | xor                 byte ptr [esi], bl
            //   46                   | inc                 esi
            //   01fb                 | add                 ebx, edi

        $sequence_11 = { 8b5514 8b12 8b4d0c 8b5d18 8b1b 4f 31c0 }
            // n = 7, score = 1100
            //   8b5514               | mov                 edx, dword ptr [ebp + 0x14]
            //   8b12                 | mov                 edx, dword ptr [edx]
            //   8b4d0c               | mov                 ecx, dword ptr [ebp + 0xc]
            //   8b5d18               | mov                 ebx, dword ptr [ebp + 0x18]
            //   8b1b                 | mov                 ebx, dword ptr [ebx]
            //   4f                   | dec                 edi
            //   31c0                 | xor                 eax, eax

        $sequence_12 = { c1e00b 3306 8b5604 0116 8b4e08 }
            // n = 5, score = 1100
            //   c1e00b               | shl                 eax, 0xb
            //   3306                 | xor                 eax, dword ptr [esi]
            //   8b5604               | mov                 edx, dword ptr [esi + 4]
            //   0116                 | add                 dword ptr [esi], edx
            //   8b4e08               | mov                 ecx, dword ptr [esi + 8]

        $sequence_13 = { c1e808 31c3 895e0c 89d8 }
            // n = 4, score = 1100
            //   c1e808               | shr                 eax, 8
            //   31c3                 | xor                 ebx, eax
            //   895e0c               | mov                 dword ptr [esi + 0xc], ebx
            //   89d8                 | mov                 eax, ebx

        $sequence_14 = { 8b1b 4f 31c0 fec2 021c16 8a0416 }
            // n = 6, score = 1100
            //   8b1b                 | mov                 ebx, dword ptr [ebx]
            //   4f                   | dec                 edi
            //   31c0                 | xor                 eax, eax
            //   fec2                 | inc                 dl
            //   021c16               | add                 bl, byte ptr [esi + edx]
            //   8a0416               | mov                 al, byte ptr [esi + edx]

        $sequence_15 = { f7e0 0fc8 01d0 894704 }
            // n = 4, score = 1100
            //   f7e0                 | mul                 eax
            //   0fc8                 | bswap               eax
            //   01d0                 | add                 eax, edx
            //   894704               | mov                 dword ptr [edi + 4], eax

        $sequence_16 = { 0f84de59ffff 3d1376110e 0f84be59ffff f7451801000000 0f8462ce0100 8b45d4 488d0c30 }
            // n = 7, score = 100
            //   0f84de59ffff         | mov                 eax, ebx
            //   3d1376110e           | inc                 esp
            //   0f84be59ffff         | mov                 edx, dword ptr [ebp + 0x48]
            //   f7451801000000       | inc                 esp
            //   0f8462ce0100         | mov                 ebx, dword ptr [ebp + 0x30]
            //   8b45d4               | shl                 eax, 7
            //   488d0c30             | inc                 ecx

        $sequence_17 = { 31d2 890c24 c744240400000000 8945f4 8955f0 e8???????? 8d0d8630d201 }
            // n = 7, score = 100
            //   31d2                 | xor                 edx, edx
            //   890c24               | mov                 dword ptr [esp], ecx
            //   c744240400000000     | mov                 dword ptr [esp + 4], 0
            //   8945f4               | mov                 dword ptr [ebp - 0xc], eax
            //   8955f0               | mov                 dword ptr [ebp - 0x10], edx
            //   e8????????           |                     
            //   8d0d8630d201         | lea                 ecx, dword ptr [0x1d23086]

        $sequence_18 = { 56 83ec28 8b450c 8b4d08 8d154e30d201 }
            // n = 5, score = 100
            //   56                   | push                esi
            //   83ec28               | sub                 esp, 0x28
            //   8b450c               | mov                 eax, dword ptr [ebp + 0xc]
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   8d154e30d201         | lea                 edx, dword ptr [0x1d2304e]

        $sequence_19 = { 5b 5d c3 8b45f0 8b0c850440d201 }
            // n = 5, score = 100
            //   5b                   | pop                 ebx
            //   5d                   | pop                 ebp
            //   c3                   | ret                 
            //   8b45f0               | mov                 eax, dword ptr [ebp - 0x10]
            //   8b0c850440d201       | mov                 ecx, dword ptr [eax*4 + 0x1d24004]

        $sequence_20 = { 44896c2428 4889f1 89442420 e8???????? 85c0 0f845724fdff 41ffc7 }
            // n = 7, score = 100
            //   44896c2428           | dec                 eax
            //   4889f1               | mov                 dword ptr [ebp - 0x38], eax
            //   89442420             | dec                 eax
            //   e8????????           |                     
            //   85c0                 | mov                 esi, eax
            //   0f845724fdff         | inc                 esp
            //   41ffc7               | mov                 eax, ecx

        $sequence_21 = { 44880d???????? 31f6 31ff 48894c2438 4531f6 4983cdff 41bc00080000 }
            // n = 7, score = 100
            //   44880d????????       |                     
            //   31f6                 | xor                 esi, esi
            //   31ff                 | xor                 edi, edi
            //   48894c2438           | dec                 eax
            //   4531f6               | mov                 dword ptr [esp + 0x38], ecx
            //   4983cdff             | inc                 ebp
            //   41bc00080000         | xor                 esi, esi

        $sequence_22 = { 4489c2 49b8????????00000000 e8???????? 4889c7 4885c0 0f84d1000000 4c01ff }
            // n = 7, score = 100
            //   4489c2               | inc                 ebp
            //   49b8????????00000000     |     
            //   e8????????           |                     
            //   4889c7               | mov                 esp, eax
            //   4885c0               | dec                 ecx
            //   0f84d1000000         | mov                 ebp, edx
            //   4c01ff               | mov                 edx, 0x1000

        $sequence_23 = { 83ec44 8b4508 8d0d2030d201 31d2 890c24 c744240400000000 }
            // n = 6, score = 100
            //   83ec44               | sub                 esp, 0x44
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8d0d2030d201         | lea                 ecx, dword ptr [0x1d23020]
            //   31d2                 | xor                 edx, edx
            //   890c24               | mov                 dword ptr [esp], ecx
            //   c744240400000000     | mov                 dword ptr [esp + 4], 0

        $sequence_24 = { 55 89e5 83ec10 8b4508 8d0d3430d201 }
            // n = 5, score = 100
            //   55                   | push                ebp
            //   89e5                 | mov                 ebp, esp
            //   83ec10               | sub                 esp, 0x10
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8d0d3430d201         | lea                 ecx, dword ptr [0x1d23034]

        $sequence_25 = { 31c9 8b55f4 8b75ec 89723c c7424003000000 }
            // n = 5, score = 100
            //   31c9                 | xor                 ecx, ecx
            //   8b55f4               | mov                 edx, dword ptr [ebp - 0xc]
            //   8b75ec               | mov                 esi, dword ptr [ebp - 0x14]
            //   89723c               | mov                 dword ptr [edx + 0x3c], esi
            //   c7424003000000       | mov                 dword ptr [edx + 0x40], 3

        $sequence_26 = { 4589c4 4989d5 e8???????? ba00100000 e8???????? 488945c8 4889c6 }
            // n = 7, score = 100
            //   4589c4               | mov                 eax, dword ptr [ebp - 0x2c]
            //   4989d5               | dec                 eax
            //   e8????????           |                     
            //   ba00100000           | lea                 ecx, dword ptr [eax + esi]
            //   e8????????           |                     
            //   488945c8             | inc                 esp
            //   4889c6               | mov                 eax, esp

        $sequence_27 = { 83c418 5e 5d c3 55 89e5 57 }
            // n = 7, score = 100
            //   83c418               | add                 esp, 0x18
            //   5e                   | pop                 esi
            //   5d                   | pop                 ebp
            //   c3                   | ret                 
            //   55                   | push                ebp
            //   89e5                 | mov                 ebp, esp
            //   57                   | push                edi

        $sequence_28 = { 4489c8 4431cb 4421d8 4c8d4df0 4431d0 31c3 41899ee0010000 }
            // n = 7, score = 100
            //   4489c8               | cmovb               eax, ecx
            //   4431cb               | mov                 ecx, eax
            //   4421d8               | mov                 dword ptr [ebp + 0x77], eax
            //   4c8d4df0             | inc                 esp
            //   4431d0               | mov                 ebx, edi
            //   31c3                 | dec                 eax
            //   41899ee0010000       | test                edi, edi

        $sequence_29 = { 4489e0 0f42c1 883d???????? 89c1 894577 4489fb 4885ff }
            // n = 7, score = 100
            //   4489e0               | ror                 edx, 5
            //   0f42c1               | je                  0xffff59e4
            //   883d????????         |                     
            //   89c1                 | cmp                 eax, 0xe117613
            //   894577               | je                  0xffff59c4
            //   4489fb               | test                dword ptr [ebp + 0x18], 1
            //   4885ff               | je                  0x1ce75

        $sequence_30 = { 448b4d40 8b5d38 89d8 448b5548 448b5d30 c1e007 41c1ca05 }
            // n = 7, score = 100
            //   448b4d40             | dec                 ecx
            //   8b5d38               | or                  ebp, 0xffffffff
            //   89d8                 | inc                 ecx
            //   448b5548             | mov                 esp, 0x800
            //   448b5d30             | inc                 esp
            //   c1e007               | mov                 ecx, dword ptr [ebp + 0x40]
            //   41c1ca05             | mov                 ebx, dword ptr [ebp + 0x38]

        $sequence_31 = { 53 56 57 83ec44 8b4508 8d0d2030d201 }
            // n = 6, score = 100
            //   53                   | push                ebx
            //   56                   | push                esi
            //   57                   | push                edi
            //   83ec44               | sub                 esp, 0x44
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8d0d2030d201         | lea                 ecx, dword ptr [0x1d23020]

    condition:
        7 of them and filesize < 2375680
}