rule win_nightsky_auto {

    meta:
        author = "Felix Bilstein - yara-signator at cocacoding dot com"
        date = "2022-11-21"
        version = "1"
        description = "Detects win.nightsky."
        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.nightsky"
        malpedia_rule_date = "20221118"
        malpedia_hash = "e0702e2e6d1d00da65c8a29a4ebacd0a4c59e1af"
        malpedia_version = "20221125"
        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 = { 4c8d0d29f80300 418bd6 4c8d05df01ffff 418bf6 488bcf e8???????? }
            // n = 6, score = 100
            //   4c8d0d29f80300       | xor                 ebx, eax
            //   418bd6               | inc                 ecx
            //   4c8d05df01ffff       | and                 ebx, 0x1f
            //   418bf6               | dec                 eax
            //   488bcf               | lea                 edx, [0x11a0b]
            //   e8????????           |                     

        $sequence_1 = { 4153 440fb7dc 311424 f8 66410fbafbfb 415b }
            // n = 6, score = 100
            //   4153                 | add                 byte ptr [eax], al
            //   440fb7dc             | sal                 di, cl
            //   311424               | dec                 esp
            //   f8                   | mov                 ecx, esp
            //   66410fbafbfb         | sal                 di, 0x25
            //   415b                 | dec                 eax

        $sequence_2 = { 410f9cc3 66440fbdd8 4803e8 f7c4ff3f8f4b 490fbae2c2 410fbaf26c }
            // n = 6, score = 100
            //   410f9cc3             | jmp                 0x30d
            //   66440fbdd8           | dec                 ebx
            //   4803e8               | xchg                dword ptr [edi + esi*8 + 0x528e0], edi
            //   f7c4ff3f8f4b         | xor                 eax, eax
            //   490fbae2c2           | dec                 eax
            //   410fbaf26c           | mov                 ebx, dword ptr [esp + 0x50]

        $sequence_3 = { 410fb6ca 44894560 45338c8d107d0500 45330f 4983c704 44894dd8 4c897df0 }
            // n = 7, score = 100
            //   410fb6ca             | inc                 ecx
            //   44894560             | mov                 dword ptr [ebx + 8], esi
            //   45338c8d107d0500     | dec                 esp
            //   45330f               | mov                 esp, esi
            //   4983c704             | dec                 ecx
            //   44894dd8             | mov                 dword ptr [ebx - 0x80], esi
            //   4c897df0             | dec                 ecx

        $sequence_4 = { 48c7442420c8000000 e8???????? 4881c700010000 4881c3c8000000 4883ee01 7588 }
            // n = 6, score = 100
            //   48c7442420c8000000     | lea    ebp, [0x158c1]
            //   e8????????           |                     
            //   4881c700010000       | cmp                 eax, ebx
            //   4881c3c8000000       | jl                  0x41b
            //   4883ee01             | jmp                 0x4a8
            //   7588                 | jmp                 0x4a2

        $sequence_5 = { 4883ec50 48c7442428feffffff 4d8be0 488bf9 488bf2 4883ce07 }
            // n = 6, score = 100
            //   4883ec50             | cmp                 eax, 6
            //   48c7442428feffffff     | ja    0x510
            //   4d8be0               | dec                 eax
            //   488bf9               | lea                 edx, [0xffff37d6]
            //   488bf2               | mov                 eax, dword ptr [edx + 4]
            //   4883ce07             | dec                 eax

        $sequence_6 = { 4883f842 72e5 4c8d85c0230000 33d2 488d4c246c ff15???????? }
            // n = 6, score = 100
            //   4883f842             | mov                 dword ptr [esp + 0x30], ebx
            //   72e5                 | inc                 ebp
            //   4c8d85c0230000       | xor                 ecx, ecx
            //   33d2                 | mov                 dword ptr [esp + 0x28], 0x8000000
            //   488d4c246c           | mov                 ecx, dword ptr [ebp - 0x20]
            //   ff15????????         |                     

        $sequence_7 = { c4c173590cc1 4c8d0d85840000 c5f359c1 c5fb101d???????? c5fb102d???????? c4e2f1a91d???????? c4e2f1a92d???????? }
            // n = 7, score = 100
            //   c4c173590cc1         | dec                 esp
            //   4c8d0d85840000       | mov                 esi, ecx
            //   c5f359c1             | mov                 edx, 8
            //   c5fb101d????????     |                     
            //   c5fb102d????????     |                     
            //   c4e2f1a91d????????     |     
            //   c4e2f1a92d????????     |     

        $sequence_8 = { 7505 488be9 eb03 4803ed b808000000 48f7e5 490f40c0 }
            // n = 7, score = 100
            //   7505                 | lea                 ecx, [0x16ab7]
            //   488be9               | jmp                 0xe93
            //   eb03                 | inc                 ebp
            //   4803ed               | mov                 ecx, eax
            //   b808000000           | dec                 esp
            //   48f7e5               | mov                 eax, edx
            //   490f40c0             | mov                 dword ptr [esp + 0x20], eax

        $sequence_9 = { 4c8b6d58 4c8d35d1a7ffff 448bd6 418bd9 418bf8 418bc4 48c1e808 }
            // n = 7, score = 100
            //   4c8b6d58             | xor                 esp, dword ptr [ebp + ecx*4 + 0x57510]
            //   4c8d35d1a7ffff       | inc                 ecx
            //   448bd6               | mov                 ecx, ebx
            //   418bd9               | dec                 ecx
            //   418bf8               | shr                 ecx, 8
            //   418bc4               | inc                 edi
            //   48c1e808             | mov                 eax, dword ptr [ebp + eax*4 + 0x57910]

    condition:
        7 of them and filesize < 19536896
}