rule win_ramsay_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.ramsay"
        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 = { 7514 ff15???????? 83f820 7502 }
            // n = 4, score = 600
            //   7514                 | jne                 0x16
            //   ff15????????         |                     
            //   83f820               | cmp                 eax, 0x20
            //   7502                 | jne                 4

        $sequence_1 = { ff15???????? 85c0 7502 eb02 ebb1 }
            // n = 5, score = 600
            //   ff15????????         |                     
            //   85c0                 | test                eax, eax
            //   7502                 | jne                 4
            //   eb02                 | jmp                 4
            //   ebb1                 | jmp                 0xffffffb3

        $sequence_2 = { 83f820 7502 eb07 33c0 }
            // n = 4, score = 600
            //   83f820               | cmp                 eax, 0x20
            //   7502                 | jne                 4
            //   eb07                 | jmp                 9
            //   33c0                 | xor                 eax, eax

        $sequence_3 = { 8b4de8 83b9a001000006 753f c745f401000000 c745f800000000 eb09 }
            // n = 6, score = 500
            //   8b4de8               | mov                 ecx, dword ptr [ebp - 0x18]
            //   83b9a001000006       | cmp                 dword ptr [ecx + 0x1a0], 6
            //   753f                 | jne                 0x41
            //   c745f401000000       | mov                 dword ptr [ebp - 0xc], 1
            //   c745f800000000       | mov                 dword ptr [ebp - 8], 0
            //   eb09                 | jmp                 0xb

        $sequence_4 = { c785c8fdffff2c020000 8d85c8fdffff 50 8b8dc4fdffff }
            // n = 4, score = 500
            //   c785c8fdffff2c020000     | mov    dword ptr [ebp - 0x238], 0x22c
            //   8d85c8fdffff         | lea                 eax, [ebp - 0x238]
            //   50                   | push                eax
            //   8b8dc4fdffff         | mov                 ecx, dword ptr [ebp - 0x23c]

        $sequence_5 = { 731e 8b45f8 3b450c 7316 8b4d08 034df8 }
            // n = 6, score = 500
            //   731e                 | jae                 0x20
            //   8b45f8               | mov                 eax, dword ptr [ebp - 8]
            //   3b450c               | cmp                 eax, dword ptr [ebp + 0xc]
            //   7316                 | jae                 0x18
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]
            //   034df8               | add                 ecx, dword ptr [ebp - 8]

        $sequence_6 = { 8b4508 8a4808 884a06 8b5508 8b4508 }
            // n = 5, score = 500
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]
            //   8a4808               | mov                 cl, byte ptr [eax + 8]
            //   884a06               | mov                 byte ptr [edx + 6], cl
            //   8b5508               | mov                 edx, dword ptr [ebp + 8]
            //   8b4508               | mov                 eax, dword ptr [ebp + 8]

        $sequence_7 = { 8b4d0c 8b11 52 8b45fc 50 6aff 8b4d08 }
            // n = 7, score = 500
            //   8b4d0c               | mov                 ecx, dword ptr [ebp + 0xc]
            //   8b11                 | mov                 edx, dword ptr [ecx]
            //   52                   | push                edx
            //   8b45fc               | mov                 eax, dword ptr [ebp - 4]
            //   50                   | push                eax
            //   6aff                 | push                -1
            //   8b4d08               | mov                 ecx, dword ptr [ebp + 8]

        $sequence_8 = { ff15???????? ebc3 8b55f8 0355fc c60200 }
            // n = 5, score = 500
            //   ff15????????         |                     
            //   ebc3                 | jmp                 0xffffffc5
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   0355fc               | add                 edx, dword ptr [ebp - 4]
            //   c60200               | mov                 byte ptr [edx], 0

        $sequence_9 = { c745ec00000000 c745f088020000 c745f400000000 6888020000 e8???????? 83c404 8945fc }
            // n = 7, score = 500
            //   c745ec00000000       | mov                 dword ptr [ebp - 0x14], 0
            //   c745f088020000       | mov                 dword ptr [ebp - 0x10], 0x288
            //   c745f400000000       | mov                 dword ptr [ebp - 0xc], 0
            //   6888020000           | push                0x288
            //   e8????????           |                     
            //   83c404               | add                 esp, 4
            //   8945fc               | mov                 dword ptr [ebp - 4], eax

        $sequence_10 = { 8945fc 6a00 6a00 8b55f8 52 }
            // n = 5, score = 500
            //   8945fc               | mov                 dword ptr [ebp - 4], eax
            //   6a00                 | push                0
            //   6a00                 | push                0
            //   8b55f8               | mov                 edx, dword ptr [ebp - 8]
            //   52                   | push                edx

        $sequence_11 = { ff15???????? 33c0 e9???????? e8???????? 85c0 7507 33c0 }
            // n = 7, score = 400
            //   ff15????????         |                     
            //   33c0                 | xor                 eax, eax
            //   e9????????           |                     
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   7507                 | jne                 9
            //   33c0                 | xor                 eax, eax

        $sequence_12 = { c644244300 c644244400 c64424454a c644244600 c644244700 }
            // n = 5, score = 200
            //   c644244300           | inc                 esp
            //   c644244400           | mov                 eax, dword ptr [esp + 0x2a0]
            //   c64424454a           | dec                 eax
            //   c644244600           | mov                 edx, dword ptr [esp + 0x298]
            //   c644244700           | mov                 byte ptr [esp + 0x43], 0

        $sequence_13 = { 4889442420 4c8b8c24a8020000 448b8424a0020000 488b942498020000 }
            // n = 4, score = 200
            //   4889442420           | dec                 eax
            //   4c8b8c24a8020000     | mov                 dword ptr [esp + 0x20], eax
            //   448b8424a0020000     | dec                 esp
            //   488b942498020000     | mov                 ecx, dword ptr [esp + 0x2a8]

        $sequence_14 = { 33c0 b901000000 f3aa c684244404000000 488d842445040000 488bf8 }
            // n = 6, score = 200
            //   33c0                 | mov                 byte ptr [esp + 0x44], 0
            //   b901000000           | mov                 byte ptr [esp + 0x45], 0x4a
            //   f3aa                 | mov                 byte ptr [esp + 0x46], 0
            //   c684244404000000     | mov                 byte ptr [esp + 0x47], 0
            //   488d842445040000     | xor                 eax, eax
            //   488bf8               | mov                 ecx, 1

        $sequence_15 = { 488d15ec0e0200 488b8c2468050000 e8???????? 488d542460 488b8c2400050000 ff15???????? }
            // n = 6, score = 200
            //   488d15ec0e0200       | rep stosb           byte ptr es:[edi], al
            //   488b8c2468050000     | mov                 byte ptr [esp + 0x444], 0
            //   e8????????           |                     
            //   488d542460           | dec                 eax
            //   488b8c2400050000     | lea                 eax, [esp + 0x445]
            //   ff15????????         |                     

    condition:
        7 of them and filesize < 2031616
}