rule win_cobalt_strike_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2020-08-17"
        version = "1"
        description = "autogenerated rule brought to you by yara-signator"
        tool = "yara-signator v0.4.0"
        tool_config = "callsandjumps;datarefs;binvalue"
        malpedia_reference = "https://malpedia.caad.fkie.fraunhofer.de/details/win.cobalt_strike"
        malpedia_rule_date = "20200817"
        malpedia_hash = "8c895fd01eccb47a6225bcb1a3ba53cbb98644c5"
        malpedia_version = "20200817"
        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 / approach 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 = { e9???????? eb0a b801000000 e9???????? }
            // n = 4, score = 1400
            //   e9????????           |                     
            //   eb0a                 | jmp                 0xc
            //   b801000000           | mov                 eax, 1
            //   e9????????           |                     

        $sequence_1 = { 3bc7 750d ff15???????? 3d33270000 }
            // n = 4, score = 1400
            //   3bc7                 | cmp                 eax, edi
            //   750d                 | jne                 0xf
            //   ff15????????         |                     
            //   3d33270000           | cmp                 eax, 0x2733

        $sequence_2 = { e8???????? e9???????? 833d????????01 7505 e8???????? }
            // n = 5, score = 1000
            //   e8????????           |                     
            //   e9????????           |                     
            //   833d????????01       |                     
            //   7505                 | lea                 ecx, [eax + ecx*4]
            //   e8????????           |                     

        $sequence_3 = { 8bd0 e8???????? 85c0 7e0e }
            // n = 4, score = 1000
            //   8bd0                 | mov                 edx, eax
            //   e8????????           |                     
            //   85c0                 | test                eax, eax
            //   7e0e                 | jle                 0x10

        $sequence_4 = { 751e 8d85dcf6ffff 50 68???????? 8d85f4faffff 56 }
            // n = 6, score = 900
            //   751e                 | cmp                 eax, 0x2733
            //   8d85dcf6ffff         | jne                 7
            //   50                   | jne                 7
            //   68????????           |                     
            //   8d85f4faffff         | jne                 7
            //   56                   | mov                 esi, 0x400

        $sequence_5 = { ff15???????? 3d33270000 7591 8b9dd8fbffff 56 e8???????? }
            // n = 6, score = 900
            //   ff15????????         |                     
            //   3d33270000           | jmp                 0xc
            //   7591                 | mov                 eax, 1
            //   8b9dd8fbffff         | cmp                 eax, edi
            //   56                   | jne                 0x11
            //   e8????????           |                     

        $sequence_6 = { 56 57 6894020000 8945ec }
            // n = 4, score = 900
            //   56                   | mov                 edx, esi
            //   57                   | dec                 eax
            //   6894020000           | mov                 edi, dword ptr [ebp + 0x50]
            //   8945ec               | mov                 ebx, eax

        $sequence_7 = { be00040000 8945f8 e8???????? 8945f0 e8???????? 8945ec }
            // n = 6, score = 900
            //   be00040000           | inc                 esp
            //   8945f8               | mov                 eax, eax
            //   e8????????           |                     
            //   8945f0               | dec                 eax
            //   e8????????           |                     
            //   8945ec               | mov                 ecx, dword ptr [ebp - 0x10]

        $sequence_8 = { 894230 8b45d4 8b4dd4 8b5014 335130 8b45d4 895034 }
            // n = 7, score = 900
            //   894230               | mov                 dword ptr [ebp - 8], eax
            //   8b45d4               | mov                 dword ptr [ebp - 0x10], eax
            //   8b4dd4               | mov                 dword ptr [ebp - 0x14], eax
            //   8b5014               | push                esi
            //   335130               | push                edi
            //   8b45d4               | push                0x294
            //   895034               | mov                 dword ptr [ebp - 0x14], eax

        $sequence_9 = { 8bc8 8a45e5 6bc90a e8???????? 03c1 6a3c }
            // n = 6, score = 900
            //   8bc8                 | mov                 edx, ebx
            //   8a45e5               | mov                 ecx, eax
            //   6bc90a               | cmp                 eax, edi
            //   e8????????           |                     
            //   03c1                 | jne                 0xf
            //   6a3c                 | cmp                 eax, 0x2733

        $sequence_10 = { 4883c204 3b0f 7ced eb09 832200 488d5204 ffc1 }
            // n = 7, score = 500
            //   4883c204             | mov                 eax, 1
            //   3b0f                 | mov                 edx, eax
            //   7ced                 | test                eax, eax
            //   eb09                 | jle                 0x12
            //   832200               | jne                 7
            //   488d5204             | jne                 7
            //   ffc1                 | jne                 7

        $sequence_11 = { 488bc1 7503 33c0 c3 4c6309 4533c0 33d2 }
            // n = 7, score = 500
            //   488bc1               | dec                 eax
            //   7503                 | mov                 edi, eax
            //   33c0                 | xor                 eax, eax
            //   c3                   | dec                 eax
            //   4c6309               | mov                 eax, ecx
            //   4533c0               | jne                 8
            //   33d2                 | xor                 eax, eax

        $sequence_12 = { 8bd6 448bc0 e8???????? e9???????? }
            // n = 4, score = 500
            //   8bd6                 | dec                 eax
            //   448bc0               | lea                 edx, [edx + 4]
            //   e8????????           |                     
            //   e9????????           |                     

        $sequence_13 = { e8???????? 448d4668 488d4da0 33d2 488bf8 e8???????? 33c0 }
            // n = 7, score = 500
            //   e8????????           |                     
            //   448d4668             | inc                 esp
            //   488d4da0             | lea                 eax, [esi + 0x68]
            //   33d2                 | dec                 eax
            //   488bf8               | lea                 ecx, [ebp - 0x60]
            //   e8????????           |                     
            //   33c0                 | xor                 edx, edx

        $sequence_14 = { 418b4c01f8 8b40f8 330a 8902 488d5204 41894c13f4 443b4304 }
            // n = 7, score = 500
            //   418b4c01f8           | ret                 
            //   8b40f8               | dec                 esp
            //   330a                 | arpl                word ptr [ecx], cx
            //   8902                 | inc                 ebp
            //   488d5204             | xor                 eax, eax
            //   41894c13f4           | xor                 edx, edx
            //   443b4304             | inc                 ecx

        $sequence_15 = { 48630b 488b4310 488d0c88 3913 }
            // n = 4, score = 500
            //   48630b               | mov                 ecx, dword ptr [ecx + eax - 8]
            //   488b4310             | mov                 eax, dword ptr [eax - 8]
            //   488d0c88             | xor                 ecx, dword ptr [edx]
            //   3913                 | mov                 dword ptr [edx], eax

    condition:
        7 of them and filesize < 696320
}